Estimating treatment effects from randomized clinical trials with noncompliance and loss to follow-up: the role of instrumental variable methods

Causal Inference Over a Subpopulation: The Effect of Malaria Vaccine in Women During Pregnancy

Preventing malaria during pregnancy is of critical importance, yet there are no approved malaria vaccines for pregnant women due to lack of efficacy results within this population. Conducting a randomized trial in pregnant women throughout the entire duration of pregnancy is impractical. Instead, a randomized trial was conducted among women of childbearing potential (WOCBP), and some participants became pregnant during the 2-year study. We explore a statistical method for estimating vaccine effect within the target subpopulation-women who can naturally become pregnant, namely, women who can become pregnant under a placebo condition-within the causal inference framework. Two vaccine effect estimators are employed to effectively utilize baseline characteristics and account for the fact that certain baseline characteristics were only available from pregnant participants. The first estimator considers all participants but can only utilize baseline variables collected from the entire participant pool. In contrast, the second estimator, which includes only pregnant participants, utilizes all available baseline information. Both estimators are evaluated numerically through simulation studies and applied to the WOCBP trial to assess vaccine effect against pregnancy malaria.

A randomized controlled trial of a self-guided mobile app targeting repetitive negative thought to prevent depression in university students: study protocol of the Nurture-U Reducing Worry prevention trial

BACKGROUND

Tackling poor mental health in university students has been identified as a priority in higher education. However, there are few evidence-based prevention initiatives designed for students. Repetitive Negative Thought (RNT, e.g. worry, rumination) is elevated in university students and is a well-established vulnerability factor for anxiety and depression. Furthermore, there are now evidence-based cognitive-behavioural interventions to tackle RNT. A mobile self-help cognitive-behavioural app targeting RNT, adapted for students may therefore be an effective, scalable, and acceptable way to improve prevention in students.

METHODS

An online single blind, two-arm parallel-group Randomised Controlled Trial (RCT) to examine the incidence of major depression and symptoms of anxiety and depression across 12 months in university students aged over 16 who screen into the study with self-reported high levels of worry and/or rumination and no current diagnosis of major depression. Eligible participants will be randomised to the active intervention arm (usual practice plus using a self-guided mobile app targeting RNT) or to the control arm (usual practice). In total, 648 participants aged over 16, with no current major depression, bipolar disorder or psychosis will be recruited from UK universities. Assessments will take place at baseline (pre-randomisation), 3 months and 12 months post- randomisation. Primary endpoint and outcome is incidence of major depression as determined by self-reported diagnostic criteria at 12-month follow-up. Depressive symptoms, anxiety, well-being, health-related quality of life, functioning and academic outcomes are secondary outcomes. Compliance, adverse events, and potentially mediating variables will be carefully monitored.

DISCUSSION

The trial aims to provide a better understanding of the causal role of tackling RNT (worry, rumination) using a self-help mobile app with respect to preventing depression in university students. This knowledge will be used to develop and disseminate innovative evidence-based, feasible, and effective mobile-health public health strategies for preventing common mental health problems.

TRIAL REGISTRATION

https://www.isrctn.com/ISRCTN86795807 Date of registration: 27 October 2022.

Identification of complier and noncomplier average causal effects in the presence of latent missing-at-random (LMAR) outcomes: a unifying view and choices of assumptions

The study of treatment effects is often complicated by noncompliance and missing data. In the one-sided noncompliance setting where of interest are the complier and noncomplier average causal effects, we address outcome missingness of the latent missing at random type (LMAR, also known as latent ignorability). That is, conditional on covariates and treatment assigned, the missingness may depend on compliance type. Within the instrumental variable (IV) approach to noncompliance, methods have been proposed for handling LMAR outcome that additionally invoke an exclusion restriction-type assumption on missingness, but no solution has been proposed for when a non-IV approach is used. This article focuses on effect identification in the presence of LMAR outcomes, with a view to flexibly accommodate different principal identification approaches. We show that under treatment assignment ignorability and LMAR only, effect nonidentifiability boils down to a set of two connected mixture equations involving unidentified stratum-specific response probabilities and outcome means. This clarifies that (except for a special case) effect identification generally requires two additional assumptions: a specific missingness mechanism assumption and a principal identification assumption. This provides a template for identifying effects based on separate choices of these assumptions. We consider a range of specific missingness assumptions, including those that have appeared in the literature and some new ones. Incidentally, we find an issue in the existing assumptions, and propose a modification of the assumptions to avoid the issue. Results under different assumptions are illustrated using data from the Baltimore Experience Corps Trial.

User engagement in clinical trials of digital mental health interventions: a systematic review

INTRODUCTION

Digital mental health interventions (DMHIs) overcome traditional barriers enabling wider access to mental health support and allowing individuals to manage their treatment. How individuals engage with DMHIs impacts the intervention effect. This review determined whether the impact of user engagement was assessed in the intervention effect in Randomised Controlled Trials (RCTs) evaluating DMHIs targeting common mental disorders (CMDs).

METHODS

This systematic review was registered on Prospero (CRD42021249503). RCTs published between 01/01/2016 and 17/09/2021 were included if evaluated DMHIs were delivered by app or website; targeted patients with a CMD without non-CMD comorbidities (e.g., diabetes); and were self-guided. Databases searched: Medline; PsycInfo; Embase; and CENTRAL. All data was double extracted. A meta-analysis compared intervention effect estimates when accounting for engagement and when engagement was ignored.

RESULTS

We identified 184 articles randomising 43,529 participants. Interventions were delivered predominantly via websites (145, 78.8%) and 140 (76.1%) articles reported engagement data. All primary analyses adopted treatment policy strategies, ignoring engagement levels. Only 19 (10.3%) articles provided additional intervention effect estimates accounting for user engagement: 2 (10.5%) conducted a complier-average-causal effect (CACE) analysis (principal stratum strategy) and 17 (89.5%) used a less-preferred per-protocol (PP) population excluding individuals failing to meet engagement criteria (estimand strategies unclear). Meta-analysis for PP estimates, when accounting for user engagement, changed the standardised effect to -0.18 95% CI (-0.32, -0.04) from - 0.14 95% CI (-0.24, -0.03) and sample sizes reduced by 33% decreasing precision, whereas meta-analysis for CACE estimates were - 0.19 95% CI (-0.42, 0.03) from - 0.16 95% CI (-0.38, 0.06) with no sample size decrease and less impact on precision. DISCUSSION: Many articles report user engagement metrics but few assessed the impact on the intervention effect missing opportunities to answer important patient centred questions for how well DMHIs work for engaged users. Defining engagement in this area is complex, more research is needed to obtain ways to categorise this into groups. However, the majority that considered engagement in analysis used approaches most likely to induce bias.

Emollient application from birth to prevent eczema in high-risk children: the BEEP RCT

Background

Atopic eczema is a common childhood skin problem linked with asthma, food allergy and allergic rhinitis that impairs quality of life.

Objectives

To determine whether advising parents to apply daily emollients in the first year can prevent eczema and/or other atopic diseases in high-risk children.

Design

A United Kingdom, multicentre, pragmatic, two-arm, parallel-group randomised controlled prevention trial with follow-up to 5 years.

Setting

Twelve secondary and four primary care centres.

Participants

Healthy infants (at least 37 weeks' gestation) at high risk of developing eczema, screened and consented during the third trimester or post delivery.

Interventions

Infants were randomised (1 : 1) within 21 days of birth to apply emollient (Doublebase Gel®; Dermal Laboratories Ltd, Hitchin, UK or Diprobase Cream®) daily to the whole body (excluding scalp) for the first year, plus standard skin-care advice (emollient group) or standard skin-care advice only (control group). Families were not blinded to allocation.

Main outcome measures

Primary outcome was eczema diagnosis in the last year at age 2 years, as defined by the UK Working Party refinement of the Hanifin and Rajka diagnostic criteria, assessed by research nurses blinded to allocation. Secondary outcomes up to age 2 years included other eczema definitions, time to onset and severity of eczema, allergic rhinitis, wheezing, allergic sensitisation, food allergy, safety (skin infections and slippages) and cost-effectiveness.

Results

One thousand three hundred and ninety-four newborns were randomised between November 2014 and November 2016; 693 emollient and 701 control. Adherence in the emollient group was 88% (466/532), 82% (427/519) and 74% (375/506) at 3, 6 and 12 months. At 2 years, eczema was present in 139/598 (23%) in the emollient group and 150/612 (25%) in controls (adjusted relative risk 0.95, 95% confidence interval 0.78 to 1.16; p = 0.61 and adjusted risk difference -1.2%, 95% confidence interval -5.9% to 3.6%). Other eczema definitions supported the primary analysis. Food allergy (milk, egg, peanut) was present in 41/547 (7.5%) in the emollient group versus 29/568 (5.1%) in controls (adjusted relative risk 1.47, 95% confidence interval 0.93 to 2.33). Mean number of skin infections per child in the first year was 0.23 (standard deviation 0.68) in the emollient group versus 0.15 (standard deviation 0.46) in controls; adjusted incidence rate ratio 1.55, 95% confidence interval 1.15 to 2.09. The adjusted incremental cost per percentage decrease in risk of eczema at 2 years was £5337 (£7281 unadjusted). No difference between the groups in eczema or other atopic diseases was observed during follow-up to age 5 years via parental questionnaires.

Limitations

Two emollient types were used which could have had different effects. The median time for starting emollients was 11 days after birth. Some contamination occurred in the control group (< 20%). Participating families were unblinded and reported on some outcomes.

Conclusions

We found no evidence that daily emollient during the first year of life prevents eczema in high-risk children. Emollient use was associated with a higher risk of skin infections and a possible increase in food allergy. Emollient use is unlikely to be considered cost-effective in this context.

Future research

To pool similar studies in an individual patient data meta-analysis.

Trial registration

This trial is registered as ISRCTN21528841.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 12/67/12) and is published in full in Health Technology Assessment; Vol. 28, No. 29. See the NIHR Funding and Awards website for further award information.

Hyperbaric Oxygen Therapy and Late Local Toxic Effects in Patients With Irradiated Breast Cancer: A Randomized Clinical Trial

Importance

Hyperbaric oxygen therapy (HBOT) is proposed as treatment for late local toxic effects after breast irradiation. Strong evidence of effectiveness is lacking.

Objective

To assess effectiveness of HBOT for late local toxic effects in women who received adjuvant radiotherapy for breast cancer.

Design, Setting, and Participants

This was a hospital-based, pragmatic, 2-arm, randomized clinical trial nested within the prospective UMBRELLA cohort following the trials within cohorts design in the Netherlands. Participants included 189 women with patient-reported moderate or severe breast, chest wall, and/or shoulder pain in combination with mild, moderate, or severe edema, fibrosis, or movement restriction 12 months or longer after breast irradiation. Data analysis was performed from May to September 2023.

Intervention

Receipt of 30 to 40 HBOT sessions over a period of 6 to 8 consecutive weeks.

Main Outcomes and Measures

Breast, chest wall, and/or shoulder pain 6 months postrandomization measured by the European Organization for Research and Treatment of Cancer QLQ-BR23 questionnaire. Secondary end points were patient-reported fibrosis, edema, movement restriction, and overall quality of life. Data were analyzed according to intention-to-treat (ITT) and complier average causal effect (CACE) principles.

Results

Between November 2019 and August 2022, 125 women (median [range] age at randomization, 56 [37-85] years) with late local toxic effects were offered to undergo HBOT (intervention arm), and 61 women (median [range] age at randomization, 60 [36-80] years) were randomized to the control arm. Of those offered HBOT, 31 (25%) accepted and completed treatment. The most common reason for not accepting HBOT was high treatment intensity. In ITT, moderate or severe pain at follow-up was reported by 58 of 115 women (50%) in the intervention arm and 32 of 52 women (62%) in the control arm (odds ratio [OR], 0.63; 95% CI, 0.32-1.23; P = .18). In CACE, the proportion of women reporting moderate or severe pain at follow-up was 32% (10 of 31) among those completing HBOT and 75% (9.7 of 12.9) among control participants expected to complete HBOT if offered (adjusted OR, 0.34; 95% CI, 0.15-0.80; P = .01). In ITT, moderate or severe fibrosis was reported by 35 of 107 (33%) in the intervention arm and 25 of 49 (51%) in the control arm (OR, 0.36; 95% CI, 0.15-0.81; P = .02). There were no significant differences in breast edema, movement restriction, and quality of life between groups in ITT and CACE.

Conclusions and Relevance

In this randomized clinical trial, offering HBOT to women with late local toxic effects was not effective for reducing pain, but was effective for reducing fibrosis. In the subgroup of women who completed HBOT, a significant reduction in pain and fibrosis was observed. A smaller than anticipated proportion of women with late local toxic effects was prepared to undergo HBOT.

Trial Registration

ClinicalTrials.gov Identifier: NCT04193722.

Sertraline for anxiety in adults with a diagnosis of autism (STRATA): study protocol for a pragmatic, multicentre, double-blind, placebo-controlled randomised controlled trial

BACKGROUND

Selective serotonin reuptake inhibitors (SSRIs) are commonly prescribed to manage anxiety in adults with an autism diagnosis. However, their effectiveness and adverse effect profile in the autistic population are not well known. This trial aims to determine the effectiveness and cost-effectiveness of the SSRI sertraline in reducing symptoms of anxiety and improving quality of life in adults with a diagnosis of autism compared with placebo and to quantify any adverse effects.

METHODS

STRATA is a two-parallel group, multi-centre, pragmatic, double-blind, randomised placebo-controlled trial with allocation at the level of the individual. It will be delivered through recruiting sites with autism services in 4 regional centres in the United Kingdom (UK) and 1 in Australia. Adults with an autism diagnosis and a Generalised Anxiety Disorder Assessment (GAD-7) score ≥ 10 at screening will be randomised 1:1 to either 25 mg sertraline or placebo, with subsequent flexible dose titration up to 200 mg. The primary outcome is GAD-7 scores at 16 weeks post-randomisation. Secondary outcomes include adverse effects, proportionate change in GAD-7 scores including 50% reduction, social anxiety, obsessive-compulsive symptoms, panic attacks, repetitive behaviours, meltdowns, depressive symptoms, composite depression and anxiety, functioning and disability and quality of life. Carer burden will be assessed in a linked carer sub-study. Outcome data will be collected using online/paper methods via video call, face-to-face or telephone according to participant preference at 16, 24 and 52 weeks post-randomisation, with brief safety checks and data collection at 1-2, 4, 8, 12 and 36 weeks. An economic evaluation to study the cost-effectiveness of sertraline vs placebo and a QuinteT Recruitment Intervention (QRI) to optimise recruitment and informed consent are embedded within the trial. Qualitative interviews at various times during the study will explore experiences of participating and taking the trial medication.

DISCUSSION

Results from this study should help autistic adults and their clinicians make evidence-based decisions on the use of sertraline for managing anxiety in this population.

TRIAL REGISTRATION

ISRCTN, ISRCTN15984604 . Registered on 08 February 2021. EudraCT 2019-004312-66. ANZCTR ACTRN12621000801819. Registered on 07 April 2021.

Statistically Adjusting for Wear Time in Randomized Trials of Continuous Glucose Monitors as a Complement to Intent-to-Treat and As-Treated Analyses: Application and Evaluation in Two Trials

Background: Randomized trials of continuous glucose monitoring (CGM) often estimate treatment effects using standard intent-to-treat (ITT) analyses. We explored how adjusting for CGM-measured wear time could complement existing analyses by estimating the effect of receiving and using CGM 100% of the time. Methods: We analyzed data from two 6-month CGM trials spanning diverse ages, the Wireless Innovation for Seniors with Diabetes Mellitus (WISDM) and CGM Intervention in Teens and Young Adults with Type 1 Diabetes (CITY) Studies. To adjust the ITT estimates for CGM use, as measured by wear time, we used an instrumental variable (IV) approach with the treatment assignment as an instrument. Outcomes included (1) time in range ([TIR] 70-180 mg/dL), time below range ([TBR] ≤70 mg/dL), and time above range ([TAR] ≥250 mg/dL). We estimated outcomes based on CGM use in the last 28 days of the trial and the full trial. Findings: In the WISDM study, the wear time rates over the 28-day window and full trial period were 93.1% (standard deviation [SD]: 20.4) and 94.5% (SD: 11.9), respectively. In the CITY study, the wear time rates over the 28-day window and full trial period were 82.2% (SD: 26.5) and 83.1% (SD: 21.5), respectively. IV-based estimates for the effect of CGM on TIR, TBR, and TAR suggested greater improvements in glycemic management than the ITT counterparts. The magnitude of the differences was proportional to the level of wear time observed in the trials. Interpretation: In trials of CGM use, the effect of variable wear time is non-negligible. By providing adherence-adjusted estimates, the IV approach may have additional utility for individual clinical decision-making.

Key considerations for choosing a statistical method to deal with incomplete treatment adherence in pragmatic trials

Pragmatic trials offer practical means of obtaining real-world evidence to help improve decision-making in comparative effectiveness settings. Unfortunately, incomplete adherence is a common problem in pragmatic trials. The commonly used methods in randomized control trials often cannot handle the added complexity imposed by incomplete adherence, resulting in biased estimates. Several naive methods and advanced causal inference methods (e.g., inverse probability weighting and instrumental variable-based approaches) have been used in the literature to deal with incomplete adherence. Practitioners and applied researchers are often confused about which method to consider under a given setting. This current work is aimed to review commonly used statistical methods to deal with non-adherence along with their key assumptions, advantages, and limitations, with a particular focus on pragmatic trials. We have listed the applicable settings for these methods and provided a summary of available software. All methods were applied to two hypothetical datasets to demonstrate how these methods perform in a given scenario, along with the R codes. The key considerations include the type of intervention strategy (point treatment settings, where treatment is administered only once versus sustained treatment settings, where treatment has to be continued over time) and availability of data (e.g., the extent of measured or unmeasured covariates that are associated with adherence, dependent confounding impacted by past treatment, and potential violation of assumptions). This study will guide practitioners and applied researchers to use the appropriate statistical method to address incomplete adherence in pragmatic trial settings for both the point and sustained treatment strategies.

Effect of Graded Sensorimotor Retraining on Pain Intensity in Patients With Chronic Low Back Pain: A Randomized Clinical Trial

IMPORTANCE

The effects of altered neural processing, defined as altering neural networks responsible for perceptions of pain and function, on chronic pain remains unclear.

OBJECTIVE

To estimate the effect of a graded sensorimotor retraining intervention (RESOLVE) on pain intensity in people with chronic low back pain.

DESIGN, SETTING, AND PARTICIPANTS

This parallel, 2-group, randomized clinical trial recruited participants with chronic (>3 months) nonspecific low back pain from primary care and community settings. A total of 276 adults were randomized (in a 1:1 ratio) to the intervention or sham procedure and attention control groups delivered by clinicians at a medical research institute in Sydney, Australia. The first participant was randomized on December 10, 2015, and the last was randomized on July 25, 2019. Follow-up was completed on February 3, 2020.

INTERVENTIONS

Participants randomized to the intervention group (n = 138) were asked to participate in 12 weekly clinical sessions and home training designed to educate them about and assist them with movement and physical activity while experiencing lower back pain. Participants randomized to the control group (n = 138) were asked to participate in 12 weekly clinical sessions and home training that required similar time as the intervention but did not focus on education, movement, and physical activity. The control group included sham laser and shortwave diathermy applied to the back and sham noninvasive brain stimulation.

MAIN OUTCOMES AND MEASURES

The primary outcome was pain intensity at 18 weeks, measured on an 11-point numerical rating scale (range, 0 [no pain] to 10 [worst pain imaginable]) for which the between-group minimum clinically important difference is 1.0 point.

RESULTS

Among 276 randomized patients (mean [SD] age, 46 [14.3] years; 138 [50%] women), 261 (95%) completed follow-up at 18 weeks. The mean pain intensity was 5.6 at baseline and 3.1 at 18 weeks in the intervention group and 5.8 at baseline and 4.0 at 18 weeks in the control group, with an estimated between-group mean difference at 18 weeks of -1.0 point ([95% CI, -1.5 to -0.4]; P = .001), favoring the intervention group.

CONCLUSIONS AND RELEVANCE

In this randomized clinical trial conducted at a single center among patients with chronic low back pain, graded sensorimotor retraining, compared with a sham procedure and attention control, significantly improved pain intensity at 18 weeks. The improvements in pain intensity were small, and further research is needed to understand the generalizability of the findings.

TRIAL REGISTRATION

ANZCTR Identifier: ACTRN12615000610538.

Cognitive remediation for people with bipolar disorder: The contribution of session attendance and therapy components to cognitive and functional outcomes

BACKGROUND

Cognitive remediation (CR) can reduce cognitive and functional difficulties in people with bipolar disorder (BD). To date, there is limited evidence on the contribution of session attendance and therapy components to treatment outcomes. This study explores whether attendance and core CR components contribute to treatment outcomes.

METHODS

This is a secondary analysis using data from a randomized controlled trial comparing CR plus treatment-as-usual (TAU; n = 40) to TAU only (n = 40) in euthymic people with BD. Session attendance was measured by number of sessions and by achieving therapy completion, pre-defined as attending ≥20 sessions. We used instrumental variable analysis to examine the effect of attendance on treatment outcomes. We then considered the association between core therapy components (i.e., massed practice, errorless learning, strategy use, therapist contact) and post-treatment outcome changes using correlation.

RESULTS

The CR group improved significantly in measure of global cognition, psychosocial functioning, and goal attainment. Therapy recipients attended 27.1 sessions on average, with 32 (80%) completing the minimum number of 20 sessions. Attending more sessions and achieving therapy completion were associated with improved treatment outcomes, but this relationship was not significant within the subgroup of CR completers. Improvement in psychosocial functioning was associated with therapist contact and goal attainment with selecting useful strategies during therapy.

CONCLUSIONS

Our findings highlight the relevance of session attendance, specifically the importance of achieving a minimum threshold of CR sessions, for outcome improvement. Strategy use and therapist contact might facilitate improvements in psychosocial functioning and personal recovery goals.

Compliance with telephone-based lifestyle weight loss programs improves low back pain but not knee pain outcomes: complier average causal effects analyses of 2 randomised trials

ABSTRACT

We conducted a complier average causal effect (CACE) analyses for 2 pragmatic randomised controlled trials. We aimed to assess the effectiveness of telephone-based lifestyle weight loss interventions compared with usual care among compliers. Participants from 2 trials with low back pain (n = 160) and knee osteoarthritis (n = 120) with a body mass index ≥27 kg/m2 were included. We defined adherence to the telephone-based lifestyle weight loss program as completing 60% (6 from 10) of telephone health coaching calls. The primary outcomes for CACE analyses were pain intensity (0-10 Numerical Rating Scale) and disability (Roland Morris Disability Questionnaire for low back pain and Western Ontario and McMaster Universities Osteoarthritis Index for knee osteoarthritis). Secondary outcomes were weight, physical activity, and diet. We used an instrumental variable approach to estimate CACE in compliers. From the intervention groups of the trials, 29% of those with low back pain (n = 23/80) and 34% of those with knee osteoarthritis (n = 20/60) complied. Complier average causal effect estimates showed potentially clinically meaningful effects, but with low certainty because of wide confidence intervals, for pain intensity (-1.4; 95% confidence interval, -3.1, 0.4) and small but also uncertain effects for disability (-2.1; 95% confidence interval, -8.6, 4.5) among compliers in the low back pain trial intervention compared with control but not in the knee osteoarthritis trial. Our findings showed that compliers of a telephone-based weight loss intervention in the low back pain trial generally had improved outcomes; however, there were inconsistent effects in compliers from the knee osteoarthritis trial. Complier average causal effect estimates were larger than intention-to-treat results but must be considered with caution.

A first step towards best practice recommendations for the design and statistical analyses of pragmatic clinical trials: a modified Delphi approach

AIM

Pragmatic clinical trials (PCTs) are randomised trials implemented through routine clinical practice, where design parameters of traditional randomised controlled trials are modified to increase generalizability. However, this may introduce statistical challenges. We aimed to identify these challenges and discuss possible solutions leading to best practice recommendations for the design and analysis of PCTs.

METHODS

A modified Delphi method was used to reach consensus among a panel of 11 experts in clinical trials and statistics. Statistical issues were identified in a focused literature review and aggregated with insights and possible solutions from expert collected through a series of survey iterations. Issues were ranked according to their importance.

RESULTS

27 articles were included and combined with experts' insight to generate a list of issues categorized into: participants; recruiting sites; randomisation, blinding and intervention; outcome (selection and measurement); and data analysis. Consensus was reached about the most important issues: risk of participants' attrition; heterogeneity of "usual care" across sites; absence of blinding; use of a subjective endpoint; and data analysis aligned with the trial estimand. Potential issues should be anticipated and preferably be addressed in the trial protocol. The experts provided solutions regarding data collection and data analysis, which were considered of equal importance.

DISCUSSION

A set of important statistical issues in PCTs was identified and approaches were suggested to anticipate and/or minimize these through data analysis. Any impact of choosing a pragmatic design feature should be gauged in the light of the trial estimand.

The UK stand together trial: protocol for a multicentre cluster randomised controlled trial to evaluate the effectiveness and cost-effectiveness of KiVa to reduce bullying in primary schools

Background

Reducing bullying is a public health priority. KiVa, a school-based anti-bullying programme, is effective in reducing bullying in Finland and requires rigorous testing in other countries, including the UK. This trial aims to test the effectiveness and cost-effectiveness of KiVa in reducing child reported bullying in UK schools compared to usual practice. The trial is currently on-going. Recruitment commenced in October 2019, however due to COVID-19 pandemic and resulting school closures was re-started in October 2020.

Methods

Design: Two-arm pragmatic multicentre cluster randomised controlled trial with an embedded process and cost-effectiveness evaluation.

Participants: 116 primary schools from four areas; North Wales, West Midlands, South East and South West England. Outcomes will be assessed at student level (ages 7–11 years; n = approximately 13,000 students).

Intervention: KiVa is a whole school programme with universal actions that places a strong emphasis on changing bystander behaviour alongside indicated actions that provide consistent strategies for dealing with incidents of bullying. KiVa will be implemented over one academic year.

Comparator: Usual practice.

Primary outcome: Student-level bullying-victimisation assessed through self-report using the extensively used and validated Olweus Bully/Victim questionnaire at baseline and 12-month follow-up.

Secondary outcomes: student-level bullying-perpetration; student mental health and emotional well-being; student level of, and roles in, bullying; school related well-being; school attendance and academic attainment; and teachers’ self-efficacy in dealing with bullying, mental well-being, and burnout.

Sample size: 116 schools (58 per arm) with an assumed ICC of 0.02 will provide 90% power to identify a relative reduction of 22% with a 5% significance level.

Randomisation: recruited schools will be randomised on 1:1 basis stratified by Key-Stage 2 size and free school meal status.

Process evaluation: assess implementation fidelity, identify influences on KiVa implementation, and examine intervention mechanisms.

Economic evaluation: Self-reported victimisation, Child Health Utility 9D, Client Service Receipt Inventory, frequency of services used, and intervention costs. The health economic analysis will be conducted from a schools and societal perspective.

Discussion

This two-arm pragmatic multicentre cluster randomised controlled trial will evaluate the KiVa anti-bullying intervention to generate evidence of the effectiveness, cost-effectiveness and scalability of the programme in the UK. Our integrated process evaluation will assess implementation fidelity, identify influences on KiVa implementation across England and Wales and examine intervention mechanisms. The integrated health economic analysis will be conducted from a schools and societal perspective. Our trial will also provide evidence regarding the programme impact on inequalities by testing whether KiVa is effective across the socio-economic gradient.

Trial registration

Trials ISRCTN 12300853 Date assigned 11/02/2020.

The clinical effectiveness of a physiotherapy delivered physical and psychological group intervention for older adults with neurogenic claudication: the BOOST randomised controlled trial

Background

Neurogenic claudication (NC) is a debilitating spinal condition affecting older adults’ mobility and quality of life.

Methods

A randomized controlled trial of 438 participants evaluated the effectiveness of a physical and psychological group intervention (BOOST program) compared to physiotherapy assessment and tailored advice (best practice advice [BPA]) for older adults with NC. Participants were identified from spinal clinics (community and secondary care) and general practice records and randomized 2:1 to the BOOST program or BPA. The primary outcome was the Oswestry Disability Index (ODI) at 12 months. Data were also collected at 6 months. Other outcomes included ODI walking item, 6-minute walk test (6MWT), and falls. The primary analysis was intention-to-treat.

Results

The average age of participants was 74.9 years (standard deviation [SD] 6.0) and 57% (246/435) were female. There was no significant difference in ODI scores between treatment groups at 12 months (adjusted mean difference [MD]: −1.4 [95% confidence intervals (CI) −4.03, 1.17]), but, at 6 months, ODI scores favored the BOOST program (adjusted MD: −3.7 [95% CI −6.27, −1.06]). At 12 months, the BOOST program resulted in greater improvements in walking capacity (6MWT MD: 21.7m [95% CI 5.96, 37.38]) and ODI walking item (MD: −0.2 [95% CI −0.45, −0.01]) and reduced falls risk (odds ratio: 0.6 [95% CI 0.40, 0.98]) compared to BPA. No serious adverse events were related to either treatment.

Conclusions

The BOOST program substantially improved mobility for older adults with NC. Future iterations of the program will consider ways to improve long-term pain-related disability.

Clinical Trials Registration Number: ISRCTN12698674

Analysis approaches to address treatment nonadherence in pragmatic trials with point-treatment settings: a simulation study

Background

Two-stage least square [2SLS] and two-stage residual inclusion [2SRI] are popularly used instrumental variable (IV) methods to address medication nonadherence in pragmatic trials with point treatment settings. These methods require assumptions, e.g., exclusion restriction, although they are known to handle unmeasured confounding. The newer IV-method, nonparametric causal bound [NPCB], showed promise in reducing uncertainty compared to usual IV-methods. The inverse probability-weighted per-protocol [IP-weighted PP] method is useful in the same setting but requires different assumptions, e.g., no unmeasured confounding. Although all of these methods are aimed to address the same nonadherence problem, comprehensive simulations to compare performances of them are absent in the literature.

Methods

We performed extensive simulations to compare the performances of the above methods in addressing nonadherence when: (1) exclusion restriction satisfied and no unmeasured confounding, (2) exclusion restriction is met but unmeasured confounding present, and (3) exclusion restriction is violated. Our simulations varied parameters such as, levels of adherence rates, unmeasured confounding, and exclusion restriction violations. Risk differences were estimated, and we compared performances in terms of bias, standard error (SE), mean squared error (MSE), and 95% confidence interval coverage probability.

Results

For setting (1), 2SLS and 2SRI have small bias and nominal coverage. IP-weighted PP outperforms these IV-methods in terms of smaller MSE but produces high MSE when nonadherence is very high. For setting (2), IP-weighted-PP generally performs poorly compared to 2SLS and 2SRI in term of bias, and both-stages adjusted IV-methods improve precision than naive IV-methods. For setting (3), IV-methods perform worst in all scenarios, and IP-weighted-PP produces unbiased estimates and small MSE when confounders are adjusted. NPCB produces larger uncertainty bound width in almost all scenarios. We also analyze a two-arm trial to estimate vitamin-A supplementation effect on childhood mortality after addressing nonadherence.

Conclusions

Understanding finite sample characteristics of these methods will guide future researchers in determining suitable analysis strategies. Since assumptions are different and often untestable for IP-weighted PP and IV methods, we suggest analyzing data using both IP-weighted PP and IV approaches in search of a robust conclusion.

Exercise to prevent shoulder problems after breast cancer surgery: the PROSPER RCT

BACKGROUND

Upper limb problems are common after breast cancer treatment.

OBJECTIVES

To investigate the clinical effectiveness and cost-effectiveness of a structured exercise programme compared with usual care on upper limb function, health-related outcomes and costs in women undergoing breast cancer surgery.

DESIGN

This was a two-arm, pragmatic, randomised controlled trial with embedded qualitative research, process evaluation and parallel economic analysis; the unit of randomisation was the individual (allocated ratio 1 : 1).

SETTING

Breast cancer centres, secondary care.

PARTICIPANTS

Women aged ≥ 18 years who had been diagnosed with breast cancer and were at higher risk of developing shoulder problems. Women were screened to identify their risk status.

INTERVENTIONS

All participants received usual-care information leaflets. Those randomised to exercise were referred to physiotherapy for an early, structured exercise programme (three to six face-to-face appointments that included strengthening, physical activity and behavioural change strategies).

MAIN OUTCOME MEASURES

The primary outcome was upper limb function at 12 months as assessed using the Disabilities of Arm, Hand and Shoulder questionnaire. Secondary outcomes were function (Disabilities of Arm, Hand and Shoulder questionnaire subscales), pain, complications (e.g. wound-related complications, lymphoedema), health-related quality of life (e.g. EuroQol-5 Dimensions, five-level version; Short Form questionnaire-12 items), physical activity and health service resource use. The economic evaluation was expressed in terms of incremental cost per quality-adjusted life-year and incremental net monetary benefit gained from an NHS and Personal Social Services perspective. Participants and physiotherapists were not blinded to group assignment, but data collectors were blinded.

RESULTS

Between 2016 and 2017, we randomised 392 participants from 17 breast cancer centres across England: 196 (50%) to the usual-care group and 196 (50%) to the exercise group. Ten participants (10/392; 3%) were withdrawn at randomisation and 32 (8%) did not provide complete baseline data. A total of 175 participants (89%) from each treatment group provided baseline data. Participants' mean age was 58.1 years (standard deviation 12.1 years; range 28-88 years). Most participants had undergone axillary node clearance surgery (327/392; 83%) and 317 (81%) had received radiotherapy. Uptake of the exercise treatment was high, with 181 out of 196 (92%) participants attending at least one physiotherapy appointment. Compliance with exercise was good: 143 out of 196 (73%) participants completed three or more physiotherapy sessions. At 12 months, 274 out of 392 (70%) participants returned questionnaires. Improvement in arm function was greater in the exercise group [mean Disabilities of Arm, Hand and Shoulder questionnaire score of 16.3 (standard deviation 17.6)] than in the usual-care group [mean Disabilities of Arm, Hand and Shoulder questionnaire score of 23.7 (standard deviation 22.9)] at 12 months for intention-to-treat (adjusted mean difference Disabilities of Arm, Hand and Shoulder questionnaire score of -7.81, 95% confidence interval -12.44 to -3.17; p = 0.001) and complier-average causal effect analyses (adjusted mean difference -8.74, 95% confidence interval -13.71 to -3.77; p ≤ 0.001). At 12 months, pain scores were lower and physical health-related quality of life was higher in the exercise group than in the usual-care group (Short Form questionnaire-12 items, mean difference 4.39, 95% confidence interval 1.74 to 7.04; p = 0.001). We found no differences in the rate of adverse events or lymphoedema over 12 months. The qualitative findings suggested that women found the exercise programme beneficial and enjoyable. Exercise accrued lower costs (-£387, 95% CI -£2491 to £1718) and generated more quality-adjusted life years (0.029, 95% CI 0.001 to 0.056) than usual care over 12 months. The cost-effectiveness analysis indicated that exercise was more cost-effective and that the results were robust to sensitivity analyses. Exercise was relatively cheap to implement (£129 per participant) and associated with lower health-care costs than usual care and improved health-related quality of life. Benefits may accrue beyond the end of the trial.

LIMITATIONS

Postal follow-up was lower than estimated; however, the study was adequately powered. No serious adverse events directly related to the intervention were reported.

CONCLUSIONS

This trial provided robust evidence that referral for early, supported exercise after breast cancer surgery improved shoulder function in those at risk of shoulder problems and was associated with lower health-care costs than usual care and improved health-related quality of life.

FUTURE WORK

Future work should focus on the implementation of exercise programmes in clinical practice for those at highest risk of shoulder problems.

TRIAL REGISTRATION

This trial is registered as ISRCTN35358984.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 15. See the NIHR Journals Library website for further project information.

Statistical methods for non-adherence in non-inferiority trials: useful and used? A systematic review

BACKGROUND

In non-inferiority trials with non-adherence to interventions (or non-compliance), intention-to-treat and per-protocol analyses are often performed; however, non-random non-adherence generally biases these estimates of efficacy.

OBJECTIVE

To identify statistical methods that adjust for the impact of non-adherence and thus estimate the causal effects of experimental interventions in non-inferiority trials.

DESIGN

A systematic review was conducted by searching the Ovid MEDLINE database (31 December 2020) to identify (1) randomised trials with a primary analysis for non-inferiority that applied (or planned to apply) statistical methods to account for the impact of non-adherence to interventions, and (2) methodology papers that described such statistical methods and included a non-inferiority trial application.

OUTCOMES

The statistical methods identified, their impacts on non-inferiority conclusions, and their advantages/disadvantages.

RESULTS

A total of 24 papers were included (4 protocols, 13 results papers and 7 methodology papers) reporting relevant methods on 26 occasions. The most common were instrumental variable approaches (n=9), including observed adherence as a covariate within a regression model (n=3), and modelling adherence as a time-varying covariate in a time-to-event analysis (n=3). Other methods included rank preserving structural failure time models and inverse-probability-of-treatment weighting. The methods identified in protocols and results papers were more commonly specified as sensitivity analyses (n=13) than primary analyses (n=3). Twelve results papers included an alternative analysis of the same outcome; conclusions regarding non-inferiority were in agreement on six occasions and could not be compared on six occasions (different measures of effect or results not provided in full).

CONCLUSIONS

Available statistical methods which attempt to account for the impact of non-adherence to interventions were used infrequently. Therefore, firm inferences about their influence on non-inferiority conclusions could not be drawn. Since intention-to-treat and per-protocol analyses do not guarantee unbiased conclusions regarding non-inferiority, the methods identified should be considered for use in sensitivity analyses.

PROSPERO REGISTRATION NUMBER

CRD42020177458.

Impact of telelactation services on breastfeeding outcomes among Black and Latinx parents: protocol for the Tele-MILC randomized controlled trial

BACKGROUND

Breastfeeding offers many medical and neurodevelopmental advantages for birthing parents and infants; however, the majority of parents stop breastfeeding before it is recommended. Professional lactation support by the International Board Certified Lactation Consultants (IBCLCs) increases breastfeeding rates; however, many communities lack access to IBCLCs. Black and Latinx parents have lower breastfeeding rates, and limited access to professional lactation support may contribute to this disparity. Virtual "telelactation" consults that use two-way video have the potential to increase access to IBCLCs among disadvantaged populations. We present a protocol for the digital Tele-MILC trial, which uses mixed methods to evaluate the impact of telelactation services on breastfeeding outcomes. The objective of this pragmatic, parallel design randomized controlled trial is to assess the impact of telelactation on breastfeeding duration and exclusivity and explore how acceptability of and experiences with telelactation vary across Latinx, Black, and non-Black and non-Latinx parents to guide future improvement of these services.

METHODS

2400 primiparous, pregnant individuals age > 18 who intend to breastfeed and live in the USA underserved by IBCLCs will be recruited. Recruitment will occur via Ovia, a pregnancy tracker mobile phone application (app) used by over one million pregnant individuals in the USA annually. Participants will be randomized to (1) on-demand telelactation video calls on personal devices or (2) ebook on infant care/usual care. Breastfeeding outcomes will be captured via surveys and interviews and compared across racial and ethnic groups. This study will track participants for 8 months (including 6 months postpartum). Primary outcomes include breastfeeding duration and breastfeeding exclusivity. We will quantify differences in these outcomes across racial and ethnic groups. Both intention-to-treat and as-treated (using instrumental variable methods) analyses will be performed. This study will also generate qualitative data on the experiences of different subgroups of parents with the telelactation intervention, including barriers to use, satisfaction, and strengths and limitations of this delivery model.

DISCUSSION

This is the first randomized study evaluating the impact of telelactation on breastfeeding outcomes. It will inform the design and implementation of future digital trials among pregnant and postpartum people, including Black and Latinx populations which are historically underrepresented in clinical trials.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04856163. Registered on April 23, 2021.

PRagMatic Pediatric Trial of Balanced vs nOrmaL Saline FlUid in Sepsis: study protocol for the PRoMPT BOLUS randomized interventional trial

Background/aims

Despite evidence that preferential use of balanced/buffered fluids may improve outcomes compared with chloride-rich 0.9% saline, saline remains the most commonly used fluid for children with septic shock. We aim to determine if resuscitation with balanced/buffered fluids as part of usual care will improve outcomes, in part through reduced kidney injury and without an increase in adverse effects, compared to 0.9% saline for children with septic shock.

Methods

The Pragmatic Pediatric Trial of Balanced versus Normal Saline Fluid in Sepsis (PRoMPT BOLUS) study is an international, open-label pragmatic interventional trial being conducted at > 40 sites in the USA, Canada, and Australia/New Zealand starting on August 25, 2020, and continuing for 5 years. Children > 6 months to < 18 years treated for suspected septic shock with abnormal perfusion in an emergency department will be randomized to receive either balanced/buffered crystalloids (intervention) or 0.9% saline (control) for initial resuscitation and maintenance fluids for up to 48 h. Eligible patients are enrolled and randomized using serially numbered, opaque envelopes concurrent with clinical care. Given the life-threatening nature of septic shock and narrow therapeutic window to start fluid resuscitation, patients may be enrolled under “exception from informed consent” in the USA or “deferred consent” in Canada and Australia/New Zealand. Other than fluid type, all decisions about timing, volume, and rate of fluid administration remain at the discretion of the treating clinicians. For pragmatic reasons, clinicians will not be blinded to study fluid type. Anticipated enrollment is 8800 patients. The primary outcome will be major adverse kidney events within 30 days (MAKE30), a composite of death, renal replacement therapy, and persistent kidney dysfunction. Additional effectiveness, safety, and biologic outcomes will also be analyzed.

Discussion

PRoMPT BOLUS will provide high-quality evidence for the comparative effectiveness of buffered/balanced crystalloids versus 0.9% saline for the initial fluid management of children with suspected septic shock in emergency settings.

Trial registration

PRoMPT BOLUS was first registered at ClinicalTrials.gov (NCT04102371) on September 25, 2019. Enrollment started on August 25, 2020.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05717-4.

Narrow-spectrum antibiotics for community-acquired pneumonia in Dutch adults (CAP-PACT): a cross-sectional, stepped-wedge, cluster-randomised, non-inferiority, antimicrobial stewardship intervention trial

BACKGROUND

Adults hospitalised to a non-intensive care unit (ICU) ward with moderately severe community-acquired pneumonia are frequently treated with broad-spectrum antibiotics, despite Dutch guidelines recommending narrow-spectrum antibiotics. Therefore, we investigated whether an antibiotic stewardship intervention would reduce the use of broad-spectrum antibiotics in patients with moderately severe community-acquired pneumonia without compromising their safety.

METHODS

In this cross-sectional, stepped-wedge, cluster-randomised, non-inferiority trial (CAP-PACT) done in 12 hospitals in the Netherlands, we enrolled immunocompetent adults (≥18 years) who were admitted to a non-ICU ward and had a working diagnosis of moderately severe community-acquired pneumonia. All participating hospitals started in a control period and every 3 months a block of two hospitals transitioned from the control to the intervention period, with all hospitals eventually ending in the intervention period. The unit of randomisation was the hospital (cluster), and electronic randomisation (by an independent data manager) decided the sequence (the time of intervention) by which hospitals would cross over from the control period to the intervention period. Blinding was not possible. The antimicrobial stewardship intervention was a bundle targeting health-care providers and comprised education, engaging opinion leaders, and prospective audit and feedback of antibiotic use. The co-primary outcomes were broad-spectrum days of therapy per patient, tested by superiority, and 90-day all-cause mortality, tested by non-inferiority with a non-inferiority margin of 3%, and were analysed in the intention-to-treat population, comprising all patients who were enrolled in the control and intervention periods. This trial was prospectively registered at ClinicalTrials.gov, NCT02604628.

FINDINGS

Between Nov 1, 2015, and Nov 1, 2017, 5683 patients were assessed for eligibility, of whom 4084 (2235 in the control period and 1849 in the intervention period) were included in the intention-to-treat analysis. The adjusted mean broad-spectrum days of therapy per patient were reduced from 6·5 days in the control period to 4·8 days in the intervention period, yielding an absolute reduction of -1·7 days (95% CI -2·4 to -1·1) and a relative reduction of 26·6% (95% CI 18·0-35·3). Crude 90-day mortality was 10·9% (242 of 2228 died) in the control period and 10·8% (199 of 1841) in the intervention period, yielding an adjusted absolute risk difference of 0·4% (90% CI -2·7 to 2·4), indicating non-inferiority.

INTERPRETATION

In patients hospitalised with moderately severe community-acquired pneumonia, a multifaceted antibiotic stewardship intervention might safely reduce broad-spectrum antibiotic use.

FUNDING

None.

Effectiveness of a Healthy Lifestyle Program (HeLP) for low back pain: statistical analysis plan for a randomised controlled trial

BACKGROUND

This paper describes the statistical analysis plan for a randomised controlled trial of a Healthy Lifestyle Program (HeLP) for low back pain targeting multiple health risks and behaviours, weight, physical activity, diet and smoking, to improve disability. We describe the methods for the main analyses and economic analysis of the trial.

METHODS AND DESIGN

The trial is a two-arm pragmatic randomised controlled trial comparing the effect of the HeLP intervention to usual care on low back pain disability at 26 weeks. A total of 346 adults with low back pain were recruited from the Newcastle and Hunter region between September 2017 and November 2019 and randomised to either HeLP or usual care. HeLP is a 6-month intervention with participant outcomes measured at weeks 6, 12, 26 and 52 post randomisation. This statistical analysis plan describes data integrity, handling and preparation of data for analyses and methods for analyses. The primary endpoint for the trial is disability at 26 weeks using the 24-item self-report Roland Morris Disability Questionnaire. The primary analysis will follow the intention-to-treat principle using linear mixed regression models.

DISCUSSION

The statistical analysis plan for this trial was produced to reduce outcome reporting bias arising from knowledge of the study findings. Any deviations will be described and justified in the final report.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry ACTRN12617001288314 . Registered on 6 September 2017.

Home-based rehabilitation programme compared with traditional physiotherapy for patients at risk of poor outcome after knee arthroplasty: the CORKA randomised controlled trial

OBJECTIVES

To evaluate whether a home-based rehabilitation programme for people assessed as being at risk of a poor outcome after knee arthroplasty offers superior outcomes to traditional outpatient physiotherapy.

DESIGN

A prospective, single-blind, two-arm randomised controlled superiority trial.

SETTING

14 National Health Service physiotherapy departments in the UK.

PARTICIPANTS

621 participants identified at high risk of a poor outcome after knee arthroplasty using a bespoke screening tool.

INTERVENTIONS

A multicomponent home-based rehabilitation programme delivered by rehabilitation assistants with supervision from qualified therapists versus usual care outpatient physiotherapy.

MAIN OUTCOME MEASURES

The primary outcome was the Late-Life Function and Disability Instrument (LLFDI) at 12 months. Secondary outcomes were the Oxford Knee Score (a disease-specific measure of function), Knee injury and Osteoarthritis Outcome Score Quality of Life subscale, Physical Activity Scale for the Elderly, 5 dimension, 5 level version of Euroqol (EQ-5D-5L) and physical function assessed using the Figure of 8 Walk test, 30 s Chair Stand Test and Single Leg Stance.

RESULTS

621 participants were randomised between March 2015 and January 2018. 309 were assigned to CORKA (Community Rehabilitation after Knee Arthroplasty) home-based rehabilitation, receiving a median five treatment sessions (IQR 4-7). 312 were assigned to usual care, receiving a median 4 sessions (IQR 2-6). The primary outcome, LLFDI function total score at 12 months, was collected for 279 participants (89%) in the home-based CORKA group and 287 participants (92%) in the usual care group. No clinically or statistically significant difference was found between the groups (intention-to-treat adjusted difference=0.49 points; 95% CI -0.89 to 1.88; p=0.48). There were no statistically significant differences between the groups on any of the patient-reported or physical secondary outcome measures at 6 or 12 months.There were 18 participants in the intervention group reporting a serious adverse event (5.8%), only one directly related to the intervention, all other adverse events recorded throughout the trial related to underlying chronic medical conditions.

CONCLUSIONS

The CORKA intervention was not superior to usual care. The trial detected no significant differences, clinical or statistical, between the two groups on either primary or secondary outcomes. CORKA offers an evaluation of an intervention utilising a different service delivery model for this patient group.

TRIAL REGISTRATION NUMBER

ISRCTN13517704.

Effects of exercise in breast cancer patients: implications of the trials within cohorts (TwiCs) design in the UMBRELLA Fit trial

Purpose

The Trials within Cohorts (TwiCs) design aims to overcome problems faced in conventional RCTs. We evaluated the TwiCs design when estimating the effect of exercise on quality of life (QoL) and fatigue in inactive breast cancer survivors.

Methods

UMBRELLA Fit was conducted within the prospective UMBRELLA breast cancer cohort. Patients provided consent for future randomization at cohort entry. We randomized inactive patients 12–18 months after cohort enrollment. The intervention group (n = 130) was offered a 12-week supervised exercise intervention. The control group (n = 130) was not informed and received usual care. Six-month exercise effects on QoL and fatigue as measured in the cohort were analyzed with intention-to-treat (ITT), instrumental variable (IV), and propensity scores (PS) analyses.

Results

Fifty-two percent (n = 68) of inactive patients accepted the intervention. Physical activity increased in patients in the intervention group, but not in the control group. We found no benefit of exercise for dimensions of QoL (ITT difference global QoL: 0.8, 95% CI = − 2.2; 3.8) and fatigue, except for a small beneficial effect on physical fatigue (ITT difference: − 1.1, 95% CI = − 1.8; − 0.3; IV: − 1.9, 95% CI = − 3.3; − 0.5, PS: − 1.2, 95% CI = − 2.3; − 0.2).

Conclusion

TwiCs gave insight into exercise intervention acceptance: about half of inactive breast cancer survivors accepted the offer and increased physical activity levels. The offer resulted in no improvement on QoL, and a small beneficial effect on physical fatigue.

Trial registration

Netherlands Trial Register (NTR5482/NL.52062.041.15), date of registration: December 07, 2015.

Zelen design clinical trials: why, when, and how

BACKGROUND

In 1979, Marvin Zelen proposed a new design for randomized clinical trials intended to facilitate clinicians' and patients' participation. The defining innovation of Zelen's proposal was random assignment of treatment prior to patient or participant consent. Following randomization, a participant would receive information and asked to consent to the assigned treatment.

METHODS

This narrative review examined recent examples of Zelen design trials evaluating clinical and public health interventions.

RESULTS

Zelen designs have often been applied to questions regarding real-world treatment or intervention effects under conditions of incomplete adherence. Examples include evaluating outreach or engagement interventions (especially for stigmatized conditions), evaluating treatments for which benefit may vary according to participant motivation, and situations when assignment to a control or usual care condition might prompt a disappointment effect. Specific practical considerations determine whether a Zelen design is scientifically appropriate or practicable. Zelen design trials usually depend on identifying participants automatically from existing records rather than by advertising, referral, or active recruitment. Assessments of baseline or prognostic characteristics usually depend on available records data rather than research-specific assessments. Because investigators must consider how exposure to treatments or interventions might bias ascertainment of outcomes, assessment of outcomes from routinely created records is often necessary. A Zelen design requires a waiver of the usual requirement for informed consent prior to random assignment of treatment. The Revised Common Rule includes specific criteria for such a waiver, and those criteria are most often met for evaluation of a low-risk and potentially beneficial intervention added to usual care. Investigators and Institutional Review Boards must also consider whether the scientific or public health benefit of a Zelen design trial outweighs the autonomy interests of potential participants. Analysis of Zelen trials compares outcomes according to original assignment, regardless of any refusal to accept or participate in the assigned treatment.

CONCLUSIONS

A Zelen design trial assesses the real-world consequences of a specific strategy to prompt or promote uptake of a specific treatment. While such trials are poorly suited to address explanatory or efficacy questions, they are often preferred for addressing pragmatic or policy questions.

Per protocol analyses produced larger treatment effect sizes than intention to treat: a meta-epidemiological study

OBJECTIVE

To undertake meta-analysis and compare treatment effects estimated by the intention-to-treat (ITT) method and per-protocol (PP) method in randomized controlled trials (RCTs). PP excludes trial participants who are non-adherent to trial protocol in terms of eligibility, interventions, or outcome assessment.

STUDY DESIGN AND SETTING

Five high impact journals were searched for all RCTs published between July 2017 to June 2019. Primary outcome was a pooled estimate that quantified the difference between the treatment effects estimated by the two methods. Results are presented as ratio of odds ratios (ROR). Meta-regression was used to explore the association between level of trial protocol non-adherence and treatment effect. Sensitivity analyses compared results with varying within-study correlations and across various study characteristics.

RESULTS

Random-effects meta-analysis (N = 156) showed that PP estimates were on average 2% greater compared to the ITT estimates (ROR: 1.02, 95% CI: 1.00-1.04, P = 0.03). The divergence further increased with higher degree of protocol non-adherence. Sensitivity analyses reassured consistent results with various within-study correlations and across various study characteristics.

CONCLUSION

There was evidence of larger treatment effect with PP compared to ITT analysis. PP analysis should not be used to assess the impact of protocol non-adherence in RCTs. Instead, in addition to ITT, investigators should consider randomization based casual method such as Complier Average Causal Effect (CACE).

Plaster cast versus functional bracing for Achilles tendon rupture: the UKSTAR RCT

BACKGROUND

Achilles tendon rupture affects > 11,000 people each year in the UK, leading to prolonged periods away from work, sports and social activities. Traditionally, the ruptured tendon is held still in a plaster cast for ≥ 8 weeks. Functional bracing is an alternative treatment that allows patients to mobilise earlier, but there is little evidence about how bracing affects patients' recovery.

OBJECTIVES

To measure the Achilles Tendon Rupture Score, quality of life, complications and resource use of patients receiving non-operative treatment for an Achilles tendon rupture treated with plaster cast compared with those treated with functional bracing.

DESIGN

This was a multicentre, randomised, pragmatic, two-group superiority trial.

SETTING

The setting was 39 NHS hospitals.

PARTICIPANTS

A total of 540 adult patients treated non-operatively for Achilles tendon rupture were randomised from July 2016 to May 2018. Exclusion criteria included presenting after 14 days, having had previous rupture and being unable to complete questionnaires.

INTERVENTIONS

A total of 266 participants had a plaster cast applied, with their toes initially pointing to the floor. The cast was changed over 8 weeks to bring the foot into a walking position. A total of 274 patients had a functional brace that facilitated immediate weight-bearing. The foot position was adjusted within the brace over the same 8-week period.

MAIN OUTCOME MEASURES

Achilles Tendon Rupture Score is patient reported and assesses symptoms and physical activity related to the Achilles tendon (score 0-100, with 100 being the best possible outcome). The secondary outcomes were quality of life, complications and resource use at 8 weeks and at 3, 6 and 9 months.

RESULTS

Participants had a mean age of 48.7 years, were predominantly male (79%) and had ruptured their tendon during sports (70%). Over 93% of participants completed follow-up. There was no statistically significant difference in Achilles Tendon Rupture Score at 9 months post injury (-1.38, 95% confidence interval -4.9 to 2.1). There was a statistically significant difference in Achilles Tendon Rupture Score at 8 weeks post injury in favour of the functional brace group (5.53, 95% confidence interval 2.0 to 9.1), but not at 3 or 6 months post injury. Quality of life showed the same pattern, with a statistically significant difference at 8 weeks post injury but not at later time points. Complication profiles were similar in both groups. Re-rupture of the tendon occurred 17 times in the plaster cast group and 13 times in the functional brace group. There was no difference in resource use.

CONCLUSIONS

This trial provides strong evidence that early weight-bearing in a functional brace provides similar outcomes to traditional plaster casting and is safe for patients receiving non-operative treatment of Achilles tendon rupture. The probability that functional bracing is cost-effective exceeds 95% for the base-case imputed analysis, assuming a cost-effectiveness threshold of £20,000 per quality-adjusted life-year. On average, functional brace is associated with lower costs (-£103, 95% confidence interval -£290 to £84) and more quality-adjusted life-years (0.015, 95% confidence interval -0.0013 to 0.030) than plaster cast.

LIMITATIONS

Some patients declined to participate in the trial, but only a small proportion of these declined because they had a preference for one treatment or another. Overall, 58% of eligible patients agreed to participate, so the participants are broadly representative of the population under investigation.

FUTURE WORK

Although the UK Study of Tendo Achilles Rehabilitation provides guidance with regard to early management, rehabilitation following Achilles tendon rupture is prolonged and further research is required to define the optimal mode of rehabilitation after the initial cast/brace has been removed.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN62639639.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 8. See the NIHR Journals Library website for further project information.

Mechanisms of rumination change in adolescent depression (RuMeChange): study protocol for a randomised controlled trial of rumination-focused cognitive behavioural therapy to reduce ruminative habit and risk of depressive relapse in high-ruminating adolescents

BACKGROUND

Adolescent-onset depression often results in a chronic and recurrent course, and is associated with worse outcomes relative to adult-onset depression. Targeting habitual depressive rumination, a specific known risk factor for relapse, may improve clinical outcomes for adolescents who have experienced a depressive episode. Randomized controlled trials (RCTs) thus far have demonstrated that rumination-focused cognitive behavioral therapy (RFCBT) reduces depressive symptoms and relapse rates in patients with residual depression and adolescents and young adults with elevated rumination. This was also observed in a pilot RCT of adolescents at risk for depressive relapse. Rumination can be measured at the self-report, behavioral, and neural levels- using patterns of connectivity between the Default Mode Network (DMN) and Cognitive Control Network (CCN). Disrupted connectivity is a putative important mechanism for understanding reduced rumination via RFCBT. A feasibility trial in adolescents found that reductions in connectivity between DMN and CCN regions following RFCBT were correlated with change in rumination and depressive symptoms.

METHOD

This is a phase III two-arm, two-stage, RCT of depression prevention. The trial tests whether RFCBT reduces identified risk factors for depressive relapse (rumination, patterns of neural connectivity, and depressive symptoms) in adolescents with partially or fully remitted depression and elevated rumination. In the first stage, RFCBT is compared to treatment as usual within the community. In the second stage, the comparator condition is relaxation therapy. Primary outcomes will be (a) reductions in depressive rumination, assessed using the Rumination Response Scale, and (b) reductions in resting state functional magnetic resonance imaging connectivity of DMN (posterior cingulate cortex) to CCN (inferior frontal gyrus), at 16 weeks post-randomization. Secondary outcomes include change in symptoms of depression following treatment, recurrence of depression over 12 months post-intervention period, and whether engagement with therapy homework (as a dose measure) is related to changes in the primary outcomes.

DISCUSSION

RFCBT will be evaluated as a putative preventive therapy to reduce the risk of depressive relapse in adolescents, and influence the identified self-report, behavioral, and neural mechanisms of change. Understanding mechanisms that underlie change in rumination is necessary to improve and further disseminate preventive interventions.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03859297 , registered 01 March 2019.

Matching depression management to severity prognosis in primary care: results of the Target-D randomised controlled trial

BACKGROUND

Mental health treatment rates are increasing, but the burden of disease has not reduced. Tools to support efficient resource distribution are required.

AIM

To investigate whether a person-centred e-health (Target-D) platform matching depression care to symptom severity prognosis can improve depressive symptoms relative to usual care.

DESIGN AND SETTING

Stratified individually randomised controlled trial in 14 general practices in Melbourne, Australia, from April 2016 to February 2019. In total, 1868 participants aged 18-65 years who had current depressive symptoms; internet access; no recent change to antidepressant; no current antipsychotic medication; and no current psychological therapy were randomised (1:1) via computer-generated allocation to intervention or usual care.

METHOD

The intervention was an e-health platform accessed in the GP waiting room, comprising symptom feedback, priority-setting, and prognosis-matched management options (online self-help, online guided psychological therapy, or nurse-led collaborative care). Management options were flexible, neither participants nor staff were blinded, and there were no substantive protocol deviations. The primary outcome was depressive symptom severity (9-item Patient Health Questionnaire [PHQ-9]) at 3 months.

RESULTS

In intention to treat analysis, estimated between- arm difference in mean PHQ-9 scores at 3 months was -0.88 (95% confidence interval [CI] = -1.45 to -0.31) favouring the intervention, and -0.59 at 12 months (95% CI = -1.18 to 0.01); standardised effect sizes of -0.16 (95% CI = -0.26 to -0.05) and -0.10 (95% CI = -0.21 to 0.002), respectively. No serious adverse events were reported.

CONCLUSION

Matching management to prognosis using a person-centred e-health platform improves depressive symptoms at 3 months compared to usual care and could feasibly be implemented at scale. Scope exists to enhance the uptake of management options.

The Moderate Alcohol and Cardiovascular Health Trial (MACH15): Design and methods for a randomized trial of moderate alcohol consumption and cardiometabolic risk

BACKGROUND

Observational studies have documented lower risks of coronary heart disease and diabetes among moderate alcohol consumers relative to abstainers, but only a randomized clinical trial can provide conclusive evidence for or against these associations.

AIM

The purpose of this study was to describe the rationale and design of the Moderate Alcohol and Cardiovascular Health Trial, aimed to assess the cardiometabolic effects of one alcoholic drink daily over an average of six years among adults 50 years or older.

METHODS

This multicenter, parallel-arm randomized trial was designed to compare the effects of one standard serving (∼11-15 g) daily of a preferred alcoholic beverage to abstention. The trial aimed to enroll 7800 people at high risk of cardiovascular disease. The primary composite endpoint comprised time to the first occurrence of non-fatal myocardial infarction, non-fatal ischemic stroke, hospitalized angina, coronary/carotid revascularization, or total mortality. The trial was designed to provide >80% power to detect a 15% reduction in the risk of the primary outcome. Secondary outcomes included diabetes. Adverse effects of special interest included injuries, congestive heart failure, alcohol use disorders, and cancer.

RESULTS

We describe the design, governance, masking issues, and data handling. In three months of field center activity until termination by the funder, the trial randomized 32 participants, successfully screened another 70, and identified ∼400 additional interested individuals.

CONCLUSIONS

We describe a feasible design for a long-term randomized trial of moderate alcohol consumption. Such a study will provide the highest level of evidence for the effects of moderate alcohol consumption on cardiovascular disease and diabetes, and will directly inform clinical and public health guidelines.

Outpatient physiotherapy versus home-based rehabilitation for patients at risk of poor outcomes after knee arthroplasty: CORKA RCT

BACKGROUND

Over 100,000 primary knee arthroplasty operations are undertaken annually in the UK. Around 15-30% of patients do not report a good outcome. Better rehabilitation strategies may improve patient-reported outcomes.

OBJECTIVES

To compare the outcomes from a traditional outpatient physiotherapy model with those from a home-based rehabilitation programme for people assessed as being at risk of a poor outcome after knee arthroplasty.

DESIGN

An individually randomised, two-arm controlled trial with a blinded outcome assessment, a parallel health economic evaluation and a nested qualitative study.

SETTING

The trial took place in 14 NHS physiotherapy departments.

PARTICIPANTS

People identified as being at high risk of a poor outcome after knee arthroplasty.

INTERVENTIONS

A multicomponent home-based rehabilitation package delivered by rehabilitation assistants with supervision from qualified therapists compared with usual-care outpatient physiotherapy.

MAIN OUTCOME MEASURES

The primary outcome was the Late Life Function and Disability Instrument at 12 months. Secondary outcomes were the Oxford Knee Score (a disease-specific measure of function); Knee injury and Osteoarthritis Outcome Score; Quality of Life subscale; Physical Activity Scale for the Elderly; EuroQol-5 Dimensions, five-level version; and physical function assessed using the Figure-of-8 Walk Test, 30-Second Chair Stand Test and Single Leg Stance. Data on the use of health-care services, time off work and informal care were collected using participant diaries.

RESULTS

In total, 621 participants were randomised. A total of 309 participants were assigned to the COmmunity based Rehabilitation after Knee Arthroplasty (CORKA) home-based rehabilitation programme, receiving a median of five treatment sessions (interquartile range 4-7 sessions). A total of 312 participants were assigned to usual care, receiving a median of four sessions (interquartile range 2-6 sessions). The primary outcome, Late Life Function and Disability Instrument function total score at 12 months, was collected for 279 participants (89%) in the home-based CORKA group and 287 participants (92%) in the usual-care group. No clinically or statistically significant difference was found between the groups (intention-to-treat adjusted difference 0.49 points, 95% confidence interval -0.89 to 1.88 points; p = 0.48). There were no statistically significant differences between the groups in any of the patient-reported or physical secondary outcome measures at 6 or 12 months post randomisation. The health economic analysis found that the CORKA intervention was cheaper to provide than usual care (£66 less per participant). Total societal costs (combining health-care costs and other costs) were lower for the CORKA intervention than usual care (£316 less per participant). Adopting a societal perspective, CORKA had a 75% probability of being cost-effective at a threshold of £30,000 per quality-adjusted life-year. Adopting the narrower health and social care perspective, CORKA had a 43% probability of being cost-effective at the same threshold.

LIMITATIONS

The interventions were of short duration and were set within current commissioning guidance for UK physiotherapy. Participants and treating therapists could not be blinded.

CONCLUSIONS

This randomised controlled trial found no important differences in outcomes when post-arthroplasty rehabilitation was delivered using a home-based, rehabilitation assistant-delivered rehabilitation package or a traditional outpatient model. However, the health economic evaluation found that when adopting a societal perspective, the CORKA home-based intervention was cost-saving and more effective than, and thus dominant over, usual care, owing to reduced time away from paid employment for this group. Further research could look at identifying the risk of poor outcome and further evaluation of a cost-effective treatment, including the workforce model to deliver it.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN13517704.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 65. See the NIHR Journals Library website for further project information.

Evaluating a Key Instrumental Variable Assumption Using Randomization Tests

Instrumental variable (IV) analyses are becoming common in health services research and epidemiology. Most IV analyses use naturally occurring instruments, such as distance to a hospital. In these analyses, investigators must assume that the instrument is as-if randomly assigned. This assumption cannot be tested directly, but it can be falsified. Most IV falsification tests compare relative prevalence or bias in observed covariates between the instrument and exposure. These tests require investigators to make covariate-by-covariate judgments about the validity of the IV design. Often, only some covariates are well-balanced, making it unclear whether as-if randomization can be assumed for the instrument. We propose an alternative falsification test that compares IV balance or bias with the balance or bias that would have been produced under randomization. A key advantage of our test is that it allows for global balance measures as well as easily interpretable graphical comparisons. Furthermore, our test does not rely on parametric assumptions and can be used to validly assess whether the instrument is significantly closer to being as-if randomized than the exposure. We demonstrate our approach using data from (SPOT)light, a prospective cohort study carried out in 48 National Health Service hospitals in the United Kingdom between November 1, 2010, and December 31, 2011. This study used bed availability in the intensive care unit as an instrument for admission to the intensive care unit.

Promotion of mental health in young adults via mobile phone app: study protocol of the ECoWeB (emotional competence for well-being in Young adults) cohort multiple randomised trials

BACKGROUND

Promoting well-being and preventing poor mental health in young people is a major global priority. Building emotional competence (EC) skills via a mobile app may be an effective, scalable and acceptable way to do this. However, few large-scale controlled trials have examined the efficacy of mobile apps in promoting mental health in young people; none have tailored the app to individual profiles.

METHOD/DESIGN

The Emotional Competence for Well-Being in Young Adults cohort multiple randomised controlled trial (cmRCT) involves a longitudinal prospective cohort to examine well-being, mental health and EC in 16-22 year olds across 12 months. Within the cohort, eligible participants are entered to either the PREVENT trial (if selected EC scores at baseline within worst-performing quartile) or to the PROMOTE trial (if selected EC scores not within worst-performing quartile). In both trials, participants are randomised (i) to continue with usual practice, repeated assessments and a self-monitoring app; (ii) to additionally receive generic cognitive-behavioural therapy self-help in app; (iii) to additionally receive personalised EC self-help in app. In total, 2142 participants aged 16 to 22 years, with no current or past history of major depression, bipolar disorder or psychosis will be recruited across UK, Germany, Spain, and Belgium. Assessments take place at baseline (pre-randomisation), 1, 3 and 12 months post-randomisation. Primary endpoint and outcome for PREVENT is level of depression symptoms on the Patient Health Questionnaire-9 at 3 months; primary endpoint and outcome for PROMOTE is emotional well-being assessed on the Warwick-Edinburgh Mental Wellbeing Scale at 3 months. Depressive symptoms, anxiety, well-being, health-related quality of life, functioning and cost-effectiveness are secondary outcomes. Compliance, adverse events and potentially mediating variables will be carefully monitored.

CONCLUSIONS

The trial aims to provide a better understanding of the causal role of learning EC skills using interventions delivered via mobile phone apps with respect to promoting well-being and preventing poor mental health in young people. This knowledge will be used to develop and disseminate innovative evidence-based, feasible, and effective Mobile-health public health strategies for preventing poor mental health and promoting well-being.

TRIAL REGISTRATION

ClinicalTrials.gov ( www.clinicaltrials.org ). Number of identification: NCT04148508 November 2019.

The assertive cardiac care trial: A randomised controlled trial of a coproduced assertive cardiac care intervention to reduce absolute cardiovascular disease risk in people with severe mental illness in the primary care setting

BACKGROUND

Cardiovascular disease (CVD) accounts for 40% of the excess mortality identified in people with severe mental illness (SMI). Modifiable CVD risk factors are higher and can be exacerbated by the cardiometabolic impact of psychotropic medications. People with SMI frequently attend primary care presenting a valuable opportunity for early identification, prevention and management of cardiovascular health. The ACCT Healthy Hearts Study will test a coproduced, nurse-led intervention delivered with general practitioners to reduce absolute CVD risk (ACVDR) at 12 months compared with an active control group.

METHODS/DESIGN

ACCT is a two group (intervention/active control) individually randomised (1:1) controlled trial (RCT). Assessments will be completed baseline (pre-randomisation), 6 months, and 12 months. The primary outcome is 5-year ACVDR measured at 12 months. Secondary outcomes include 6-month ACVDR; and blood pressure, lipids, HbA1c, BMI, quality of life, physical activity, motivation to change health behaviour, medication adherence, alcohol use and hospitalisation at 6 and 12 months. Linear mixed-effects regression will estimate mean difference between groups for primary and secondary continuous outcomes. Economic cost-consequences analysis will be conducted using quality of life and health resource use information and routinely collected government health service use and medication data. A parallel process evaluation will investigate implementation of the intervention, uptake and outcomes.

DISCUSSION

ACCT will deliver a coproduced and person-centred, guideline level cardiovascular primary care intervention to a high need population with SMI. If successful, the intervention could lead to the reduction of the mortality gap and increase opportunities for meaningful social and economic participation. Trial registration ANZCTR Trial number: ACTRN12619001112156.

Comparison of As-Needed and Scheduled Posthospitalization Follow-up for Children Hospitalized for Bronchiolitis: The Bronchiolitis Follow-up Intervention Trial (BeneFIT) Randomized Clinical Trial

Importance

Posthospitalization follow-up visits are prescribed frequently for children with bronchiolitis. The rationale for this practice is unclear, but prior work has indicated that families value these visits for the reassurance provided. The overall risks and benefits of scheduled visits have not been evaluated.

Objective

To assess whether an as-needed posthospitalization follow-up visit is noninferior to a scheduled posthospitalization follow-up visit with respect to reducing anxiety among parents of children hospitalized for bronchiolitis.

Design, Setting, and Participants

This open-label, noninferiority randomized clinical trial, performed between January 1, 2018, and April 31, 2019, assessed children younger than 24 months of age hospitalized for bronchiolitis at 2 children's hospitals (Primary Children's Hospital, Salt Lake City, Utah, and Lucile Packard Children's Hospital, Palo Alto, California) and 2 community hospitals (Intermountain Riverton Hospital, Riverton, Utah, and Packard El Camino Hospital, Mountain View, California). Data analysis was performed in an intention-to-treat manner.

Interventions

Randomization (1:1) to a scheduled (n = 151) vs an as-needed (n = 153) posthospitalization follow-up visit.

Main Outcome and Measures

The primary outcome was parental anxiety 7 days after hospital discharge, measured using the anxiety portion of the Hospital Anxiety and Depression Scale, which ranged from 0 to 28 points, with higher scores indicating greater anxiety. Fourteen prespecified secondary outcomes were assessed.

Results

Among 304 children randomized (median age, 8 months; interquartile range, 3-14 months; 179 [59%] male), the primary outcome was available for 269 patients (88%). A total of 106 children (81%) in the scheduled follow-up group attended a scheduled posthospitalization visit compared with 26 children (19%) in the as-needed group (absolute difference, 62%; 95% CI, 53%-71%). The mean (SD) 7-day parental anxiety score was 3.9 (3.5) among the as-needed posthospitalization follow-up group and 4.2 (3.5) among the scheduled group (absolute difference, -0.3 points; 95% CI, -1.0 to 0.4 points), with the upper bound of the 95% CI within the prespecified noninferiority margin of 1.1 points. Aside from a decreased mean number of clinic visits (absolute difference, -0.6 visits per patient; 95% CI, -0.4 to -0.8 visits per patient) among the as-needed group, there were no significant between-group differences in secondary outcomes, including readmissions (any hospital readmission before symptom resolution: absolute difference, -1.6%; 95% CI, -5.7% to 2.5%) and symptom duration (time from discharge to cough resolution: absolute difference, -0.6 days; 95% CI, -2.4 to 1.2 days; time from discharge to child reported "back to normal": absolute difference, -0.8 days; 95% CI, -2.7 to 1.0 days; and time from discharge to symptom resolution: absolute difference, -0.6 days; 95% CI, -2.5 to 1.3 days).

Conclusions and Relevance

Among parents of children hospitalized for bronchiolitis, an as-needed posthospitalization follow-up visit is noninferior to a scheduled posthospitalization follow-up visit with respect to reducing parental anxiety. These findings support as-needed follow-up as an effective posthospitalization follow-up strategy.

Trial Registration

ClinicalTrials.gov Identifier: NCT03354325.

Better Outcomes for Older people with Spinal Trouble (BOOST) trial: statistical analysis plan for a randomised controlled trial of a combined physical and psychological intervention for older adults with neurogenic claudication

BACKGROUND

Neurogenic claudication is a common spinal condition affecting older adults that has a major effect on mobility and implicitly independence. The effectiveness of conservative interventions in this population is not known. We describe the statistical analysis plan for the Better Outcomes for Older people with Spinal trouble (BOOST) randomised controlled trial.

METHODS/DESIGN

BOOST is a pragmatic, multicentre, parallel, two-arm, randomised controlled trial. Participants are community-dwelling adults, 65 years or older, with neurogenic claudication, registered prospectively, and randomised 2:1 (intervention to control) to the combined physical and psychological BOOST group physiotherapy programme or best practice advice. The primary outcome is the Oswestry Disability Index at 12 months. Secondary outcomes include the Short Physical Performance Battery, Swiss Spinal Stenosis Scale, 6 Minute Walk Test, Fear Avoidance Beliefs Questionnaire, and Tilburg Frailty Indicator. Outcomes are measured at 6 and 12 months by researchers blinded to treatment allocation. The primary statistical analysis is by intention to treat. Further study design details are published in the BOOST protocol.

DISCUSSION

The planned statistical analyses for the BOOST trial aim to reduce the risk of outcome reporting bias from prior data knowledge. Any changes or deviations from this statistical analysis plan will be described and justified in the final study report.

TRIAL REGISTRATION

This study has been registered in the International Standard Randomised Controlled Trial Number registry, reference number ISRCTN12698674 . Registered on 10 November 2015.

How the EMERGE guideline on medication adherence can improve the quality of clinical trials

Medication adherence in drug trials is suboptimal, affecting the quality of these studies and adding significant costs. Nonadherence in this setting can lead to null findings, unduly large sample sizes and the need for dose modification after a drug has been approved. Despite these drawbacks, adherence behaviours are not consistently measured, analysed or reported appropriately in trial settings. The ESPACOMP Medication Adherence Reporting Guideline (EMERGE) offers a solution by facilitating a sound protocol design that takes this crucial factor into account. This article summarises key evidence on traditional and newer measurements of adherence, discusses implementation in clinical trial settings and makes recommendations about the analysis and interpretation of adherence data. Given the potential benefits of this approach, the authors call on regulators and the pharmaceutical industry to endorse the EMERGE guideline.

Plaster cast versus functional brace for non-surgical treatment of Achilles tendon rupture (UKSTAR): a multicentre randomised controlled trial and economic evaluation

BACKGROUND

Patients with Achilles tendon rupture who have non-operative treatment have traditionally been treated with immobilisation of the tendon in plaster casts for several weeks. Functional bracing is an alternative non-operative treatment that allows earlier mobilisation, but evidence on its effectiveness and safety is scarce. The aim of the UKSTAR trial was to compare functional and quality-of-life outcomes and resource use in patients treated non-operatively with plaster cast versus functional brace.

METHODS

UKSTAR was a pragmatic, superiority, multicentre, randomised controlled trial done at 39 hospitals in the UK. Patients (aged ≥16 years) who were being treated non-operatively for a primary Achilles tendon rupture at the participating centres were potentially eligible. The exclusion criteria were presenting more than 14 days after injury, previous rupture of the same Achilles tendon, or being unable to complete the questionnaires. Eligible participants were randomly assigned (1:1) to receive a plaster cast or functional brace using a centralised web-based system. Because the interventions were clearly visible, neither patients nor clinicians could be masked. Participants wore the intervention for 8 weeks. The primary outcome was patient-reported Achilles tendon rupture score (ATRS) at 9 months, analysed in the modified intention-to-treat population (all patients in the groups to which they were allocated, excluding participants who withdrew or died before providing any outcome data). The main safety outcome was the incidence of tendon re-rupture. Resource use was recorded from a health and personal social care perspective. The trial is registered with ISRCTN, ISRCTN62639639.

FINDINGS

Between Aug 15, 2016, and May 31, 2018, 1451 patients were screened, of whom 540 participants (mean age 48·7 years, 79% male) were randomly allocated to receive plaster cast (n=266) or functional brace (n=274). 527 (98%) of 540 were included in the modified intention-to-treat population, and 13 (2%) were excluded because they withdrew or died before providing any outcome data. There was no difference in ATRS at 9 months post injury (cast group n=244, mean ATRS 74∙4 [SD 19∙8]; functional brace group n=259, ATRS 72∙8 [20∙4]; adjusted mean difference -1∙38 [95% CI -4∙9 to 2∙1], p=0·44). There was no difference in the rate of re-rupture of the tendon (17 [6%] of 266 in the plaster cast group vs 13 [5%] of 274 in the functional brace group, p=0·40). The mean total health and personal social care cost was £1181 for the plaster cast group and £1078 for the functional bract group (mean between-group difference -£103 [95% CI -289 to 84]).

INTERPRETATION

Traditional plaster casting was not found to be superior to early weight-bearing in a functional brace, as measured by ATRS, in the management of patients treated non-surgically for Achilles tendon rupture. Clinicians may consider the use of early weight-bearing in a functional brace as a safe and cost-effective alternative to plaster casting.

FUNDING

UK National Institute for Health Research Health Technology Assessment Programme.

A health promotion intervention to improve lifestyle choices and health outcomes in people with psychosis: a research programme including the IMPaCT RCT

Background

People with psychotic disorders have reduced life expectancy largely because of physical health problems, especially cardiovascular disease, that are complicated by the use of tobacco and cannabis.

Objectives

We set out to (1) chart lifestyle and substance use choices and the emergence of cardiometabolic risk from the earliest presentation with psychosis, (2) develop a pragmatic health promotion intervention integrated within the clinical teams to improve the lifestyle choices and health outcomes of people with psychosis and (3) evaluate the clinical effectiveness and cost-effectiveness of that health promotion intervention.

Design

We performed a longitudinal cohort study of people presenting with their first episode of psychosis in three mental health trusts and followed up participants for 1 year [work package 1, physical health and substance use measures in first episode of psychosis (PUMP)]. We used an iterative Delphi methodology to develop and refine a modular health promotion intervention, improving physical health and reducing substance use in psychosis (IMPaCT) therapy, which was to be delivered by the patient’s usual care co-ordinator and used motivational interviewing techniques and cognitive–behavioural therapy to improve health choices of people with psychosis (work package 2). We then conducted a multicentre, two-arm, parallel-cluster, randomised controlled trial to determine the clinical effectiveness and cost-effectiveness of using the intervention with people with established psychosis (work package 3: IMPaCT randomised controlled trial) in five UK mental health trusts. The work took place between 2008 and 2014.

Participants

All people aged between 16 and 65 years within 6 months of their first presentation with a non-organic psychosis and who were proficient in English were eligible for inclusion in the PUMP study. Participants in the work package 2 training development were staff selected from a range of settings, working with psychosis. Participants in the phase 3 Delphi consensus and manual development comprised three expert groups of (1) therapists/researchers recruited from the local and national community, (2) clinicians and (3) service users, each of whom took part in two iterative review and feedback sessions. For work package 3, IMPaCT randomised controlled trial, care co-ordinators in participating community mental health teams who were permanently employed and had a minimum of four eligible patients (i.e. aged between 18 and 65 years with a diagnosis of a psychotic disorder) on their caseload were eligible to participate. In studies 1 and 3, patient participants were ineligible if they were pregnant or had a major illness that would have had an impact on their metabolic status or if they had a significant learning disability. All participants were included in the study only after giving written confirmed consent.

Main outcome measures

Cardiometabolic risk markers, including rates of obesity and central obesity, and levels of glycated haemoglobin (HbA1c) and lipids, were the main outcomes in work package 1 (PUMP), with descriptive data presented on substance use. Our primary outcome measure for the IMPaCT randomised controlled trial was the physical or mental health component Short Form questionnaire-36 items quality-of-life scores at 12 months.

Results

Obesity rates rose from 18% at first presentation with psychosis to 24% by 1 year, but cardiometabolic risk was not associated with baseline lifestyle and substance use choices. Patterns of increase in the levels of HbA1c over the year following first presentation showed variation by ethnic group. We recruited 104 care co-ordinators, of whom 52 (with 213 patients) were randomised to deliver IMPaCT therapy and 52 (with 193 patients) were randomised to deliver treatment as usual, in keeping with our power calculations. Of these 406 participants with established psychosis, 318 (78%) and 301 (74%) participants, respectively, attended the 12- and 15-month follow-ups. We found no significant effect of IMPaCT therapy compared with treatment as usual on the physical or mental health component Short Form questionnaire-36 items scores at either time point in an intention-to-treat analysis [physical health score (‘d’) –0.17 at 12 months and –0.09 at 15 months; mental health score (‘d’) 0.03 at 12 months and –0.05 at 15 months] or on costs. Nor did we find an effect on other cardiovascular risk indicators, including diabetes, except in the case of high-density lipoprotein cholesterol, which showed a trend for greater benefit with IMPaCT therapy than with treatment as usual (treatment effect 0.085, 95% confidence interval 0.007 to 0.16; p = 0.034).

Limitations

Follow-up in work package 1 was challenging, with 127 out of 293 participants attending; however, there was no difference in cardiometabolic measures or demographic factors at baseline between those who attended for follow-up and those who did not. In work package 3, the IMPaCT randomised controlled trial, care co-ordinators struggled to provide additional time to their patients that was devoted to the health promotion intervention on top of their usual clinical care contact with them.

Conclusions

Cardiometabolic risk is prominent even soon after first presentation with psychosis and increases over time. Lifestyle choices and substance use habits at first presentation do not predict those who will be most cardiometabolically compromised 1 year later. Training and supervising care co-ordinators to deliver a health promotion intervention to their own patients on top of routine care is not effective in the NHS for improving quality of life or reducing cardiometabolic risk.

Future work

Further work is needed to develop and evaluate effective, cost-effective and affordable ways of preventing the emergence of and reversing existing cardiometabolic risk indicators in people with psychosis.

Trial registration

Current Controlled Trials ISRCTN58667926.

Funding

This project was funded by the National Institute for Health Research (NIHR) Programme Grants for Applied Research programme and will be published in full in Programme Grants for Applied Research; Vol. 8, No. 1. See the NIHR Journals Library website for further project information.

Supplemental MRI Screening for Women with Extremely Dense Breast Tissue

BACKGROUND

Extremely dense breast tissue is a risk factor for breast cancer and limits the detection of cancer with mammography. Data are needed on the use of supplemental magnetic resonance imaging (MRI) to improve early detection and reduce interval breast cancers in such patients.

METHODS

In this multicenter, randomized, controlled trial in the Netherlands, we assigned 40,373 women between the ages of 50 and 75 years with extremely dense breast tissue and normal results on screening mammography to a group that was invited to undergo supplemental MRI or to a group that received mammography screening only. The groups were assigned in a 1:4 ratio, with 8061 in the MRI-invitation group and 32,312 in the mammography-only group. The primary outcome was the between-group difference in the incidence of interval cancers during a 2-year screening period.

RESULTS

The interval-cancer rate was 2.5 per 1000 screenings in the MRI-invitation group and 5.0 per 1000 screenings in the mammography-only group, for a difference of 2.5 per 1000 screenings (95% confidence interval [CI], 1.0 to 3.7; P<0.001). Of the women who were invited to undergo MRI, 59% accepted the invitation. Of the 20 interval cancers that were diagnosed in the MRI-invitation group, 4 were diagnosed in the women who actually underwent MRI (0.8 per 1000 screenings) and 16 in those who did not accept the invitation (4.9 per 1000 screenings). The MRI cancer-detection rate among the women who actually underwent MRI screening was 16.5 per 1000 screenings (95% CI, 13.3 to 20.5). The positive predictive value was 17.4% (95% CI, 14.2 to 21.2) for recall for additional testing and 26.3% (95% CI, 21.7 to 31.6) for biopsy. The false positive rate was 79.8 per 1000 screenings. Among the women who underwent MRI, 0.1% had either an adverse event or a serious adverse event during or immediately after the screening.

CONCLUSIONS

The use of supplemental MRI screening in women with extremely dense breast tissue and normal results on mammography resulted in the diagnosis of significantly fewer interval cancers than mammography alone during a 2-year screening period. (Funded by the University Medical Center Utrecht and others; DENSE ClinicalTrials.gov number, NCT01315015.).

Preventing child mental health problems through parenting interventions in Southeastern Europe (RISE): Protocol for a multi-country cluster randomized factorial study

BACKGROUND

Child mental health problems continue to be a major global concern, especially in low- and middle-income countries (LMICs). Parenting interventions have been shown to be effective for reducing child behavior problems in high-income countries, with emerging evidence supporting similar effects in LMICs. However, there remain substantial barriers to scaling up evidence-based interventions due to limited human and financial resources in such countries.

METHODS

This protocol is for a multi-center cluster randomized factorial trial of an evidence-based parenting intervention, Parenting for Lifelong Health for Young Children, for families with children ages 2-9 years with subclinical levels of behavior problems in three Southeastern European countries, Republic of Moldova, North Macedonia, and Romania (8 conditions, 48 clusters, 864 families, 108 per condition). The trial will test three intervention components: length (5 vs. 10 sessions), engagement (basic vs. enhanced package), and fidelity (on-demand vs. structured supervision). Primary outcomes are child aggressive behavior, dysfunctional parenting, and positive parenting. Analyses will examine the main effect and cost-effectiveness of each component, as well as potential interaction effects between components, in order to identify the most optimal combination of program components.

DISCUSSION

This study is the first factorial experiment of a parenting program in LMICs. Findings will inform the subsequent testing of the optimized program in a multisite randomized controlled trial in 2021.

TRIAL REGISTRATION

NCT03865485 registered in ClinicalTrials.gov on March 5, 2019.

Practical help for specifying the target difference in sample size calculations for RCTs: the DELTA2 five-stage study, including a workshop

BACKGROUND

The randomised controlled trial is widely considered to be the gold standard study for comparing the effectiveness of health interventions. Central to its design is a calculation of the number of participants needed (the sample size) for the trial. The sample size is typically calculated by specifying the magnitude of the difference in the primary outcome between the intervention effects for the population of interest. This difference is called the 'target difference' and should be appropriate for the principal estimand of interest and determined by the primary aim of the study. The target difference between treatments should be considered realistic and/or important by one or more key stakeholder groups.

OBJECTIVE

The objective of the report is to provide practical help on the choice of target difference used in the sample size calculation for a randomised controlled trial for researchers and funder representatives.

METHODS

The Difference ELicitation in TriAls2 (DELTA2) recommendations and advice were developed through a five-stage process, which included two literature reviews of existing funder guidance and recent methodological literature; a Delphi process to engage with a wider group of stakeholders; a 2-day workshop; and finalising the core document.

RESULTS

Advice is provided for definitive trials (Phase III/IV studies). Methods for choosing the target difference are reviewed. To aid those new to the topic, and to encourage better practice, 10 recommendations are made regarding choosing the target difference and undertaking a sample size calculation. Recommended reporting items for trial proposal, protocols and results papers under the conventional approach are also provided. Case studies reflecting different trial designs and covering different conditions are provided. Alternative trial designs and methods for choosing the sample size are also briefly considered.

CONCLUSIONS

Choosing an appropriate sample size is crucial if a study is to inform clinical practice. The number of patients recruited into the trial needs to be sufficient to answer the objectives; however, the number should not be higher than necessary to avoid unnecessary burden on patients and wasting precious resources. The choice of the target difference is a key part of this process under the conventional approach to sample size calculations. This document provides advice and recommendations to improve practice and reporting regarding this aspect of trial design. Future work could extend the work to address other less common approaches to the sample size calculations, particularly in terms of appropriate reporting items.

FUNDING

Funded by the Medical Research Council (MRC) UK and the National Institute for Health Research as part of the MRC-National Institute for Health Research Methodology Research programme.

Healthy Lifestyle Program (HeLP) for low back pain: protocol for a randomised controlled trial

INTRODUCTION

Low back pain is one of the most common and burdensome chronic conditions worldwide. Lifestyle factors, such as excess weight, physical inactivity, poor diet and smoking, are linked to low back pain chronicity and disability. There are few high-quality randomised controlled trials that investigate the effects of targeting lifestyle risk factors in people with chronic low back pain.

METHODS AND ANALYSIS

The aim of this study is to determine the effectiveness of a Healthy Lifestyle Program (HeLP) for low back pain targeting weight, physical activity, diet and smoking to reduce disability in patients with chronic low back pain compared with usual care. This is a randomised controlled trial, with participants stratified by body mass index, allocated 1:1 to the HeLP intervention or usual physiotherapy care. HeLP involves three main components: (1) clinical consultations with a physiotherapist and dietitian; (2) educational resources; and (3) telephone-based health coaching support for lifestyle risk factors. The primary outcome is disability (Roland Morris Disability Questionnaire) at 26 weeks. Secondary outcomes include pain intensity, weight, quality of life and smoking status. Data will be collected at baseline, and at weeks 6, 12, 26 and 52. Patients with chronic low back pain who have at least one health risk factor (are overweight or obese, are smokers and have inadequate physical activity or fruit and vegetable consumption) will be recruited from primary or secondary care, or the community. Primary outcome data will be analysed by intention to treat using linear mixed-effects regression models. We will conduct three supplementary analyses: causal mediation analysis, complier average causal effects analysis and economic analysis.

ETHICS AND DISSEMINATION

This study was approved by the Hunter New England Research Ethics Committee (Approval No 17/02/15/4.05), and the University of Newcastle Human Research Ethics Committee (Ref No H-2017-0222). Outcomes of this trial and supplementary analyses will be disseminated through publications in peer-reviewed journals and conference presentations.

TRIAL REGISTRATION NUMBER

ACTRN12617001288314.

Exercise or manual physiotherapy compared with a single session of physiotherapy for osteoporotic vertebral fracture: three-arm PROVE RCT

BACKGROUND

A total of 25,000 people in the UK have osteoporotic vertebral fracture (OVF). Evidence suggests that physiotherapy may have an important treatment role.

OBJECTIVE

The objective was to investigate the clinical effectiveness and cost-effectiveness of two different physiotherapy programmes for people with OVF compared with a single physiotherapy session.

DESIGN

This was a prospective, adaptive, multicentre, assessor-blinded randomised controlled trial (RCT) with nested qualitative and health economic studies.

SETTING

This trial was based in 21 NHS physiotherapy departments.

PARTICIPANTS

The participants were people with symptomatic OVF.

INTERVENTIONS

Seven sessions of either manual outpatient physiotherapy or exercise outpatient physiotherapy compared with the best practice of a 1-hour single session of physiotherapy (SSPT).

MAIN OUTCOME MEASURES

Outcomes were measured at 4 and 12 months. The primary outcomes were quality of life and muscle endurance, which were measured by the disease-specific QUALEFFO-41 (Quality of Life Questionnaire of the European Foundation for Osteoporosis - 41 items) and timed loaded standing (TLS) test, respectively. Secondary outcomes were (1) thoracic kyphosis angle, (2) balance, evaluated via the functional reach test (FRT), and (3) physical function, assessed via the Short Physical Performance Battery (SPPB), 6-minute walk test (6MWT), Physical Activity Scale for the Elderly, a health resource use and falls diary, and the EuroQol-5 Dimensions, five-level version.

RESULTS

A total of 615 participants were enrolled, with 216, 203 and 196 randomised by a computer-generated program to exercise therapy, manual therapy and a SSPT, respectively. Baseline data were available for 613 participants, 531 (86.6%) of whom were women; the mean age of these participants was 72.14 years (standard deviation 9.09 years). Primary outcome data were obtained for 69% of participants (429/615) at 12 months: 175 in the exercise therapy arm, 181 in the manual therapy arm and 173 in the SSPT arm. Interim analysis met the criteria for all arms to remain in the study. For the primary outcomes at 12 months, there were no significant benefits over SSPT of exercise [QUALEFFO-41, difference -0.23 points, 95% confidence interval (CI) -3.20 to 1.59 points; p = 1.000; and TLS test, difference 5.77 seconds, 95% CI -4.85 to 20.46 seconds; p = 0.437] or of manual therapy (QUALEFFO-41, difference 1.35 points, 95% CI -1.76 to 2.93 points; p = 0.744; TLS test, difference 9.69 seconds (95% CI 0.09 to 24.86 seconds; p = 0.335). At 4 months, there were significant gains for both manual therapy and exercise therapy over SSPT in the TLS test in participants aged < 70 years. Exercise therapy was superior to a SSPT at 4 months in the SPPB, FRT and 6MWT and manual therapy was superior to a SSPT at 4 months in the TLS test and FRT. Neither manual therapy nor exercise therapy was cost-effective relative to a SSPT using the threshold of £20,000 per quality-adjusted life-year. There were no treatment-related serious adverse events.

CONCLUSIONS

This is the largest RCT to date assessing physiotherapy in participants with OVFs. At 1 year, neither treatment intervention conferred more benefit than a single 1-hour physiotherapy advice session. The focus of future work should be on the intensity and duration of interventions to determine if changes to these would demonstrate more sustained effects.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN49117867.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 44. See the NIHR Journals Library website for further project information.

Cast versus functional brace in the rehabilitation of patients with a rupture of the Achilles tendon: statistical analysis plan for the UK study of tendo Achilles rehabilitation (UK STAR) multi-centre randomised controlled trial

Background

The incidence of Achilles tendon rupture in the UK is increasing and the best rehabilitation strategy for patients treated non-operatively remains unclear. We describe a statistical analysis plan (SAP) for the UK study of tendo Achilles rehabilitation (UK STAR) multi-centre randomised trial.

Methods/design

UK STAR is a 1:1, multi-centre, parallel, two-arm, superiority randomised controlled trial. This study aims to evaluate the use of functional bracing compared to plaster cast for the management of acute Achilles tendon rupture in adult patients treated non-operatively. The primary outcome is the Achilles Tendon Rupture Score measured at 9 months after injury and will be estimated based on a linear mixed effects regression model adjusted for the stratification factor (centre) and other key prognostic variables. Secondary outcomes include complications, quality of life and resource use evaluated at 8 weeks and at 3, 6 and 9 months after the injury. Missing data will be summarised and reported by treatment arm. Full details of the planned analysis methods are described in this paper. Further study design details are published in the UK STAR protocol.

Discussion

The planned statistical analyses for UK STAR aim to reduce the risk of outcome reporting bias arising from prior data knowledge. Any changes or deviations from the current SAP will be described and justified in the final study report.

Trial registration

International Standard Randomised Controlled Trial Number Registry, ISRCTN62639639. Registered on 22 June 2016.

Combining mirtazapine with SSRIs or SNRIs for treatment-resistant depression: the MIR RCT

BACKGROUND

Depression is usually managed in primary care and antidepressants are often the first-line treatment, but only half of those treated respond to a single antidepressant.

OBJECTIVES

To investigate whether or not combining mirtazapine with serotonin-noradrenaline reuptake inhibitor (SNRI) or selective serotonin reuptake inhibitor (SSRI) antidepressants results in better patient outcomes and more efficient NHS care than SNRI or SSRI therapy alone in treatment-resistant depression (TRD).

DESIGN

The MIR trial was a two-parallel-group, multicentre, pragmatic, placebo-controlled randomised trial with allocation at the level of the individual.

SETTING

Participants were recruited from primary care in Bristol, Exeter, Hull/York and Manchester/Keele.

PARTICIPANTS

Eligible participants were aged ≥ 18 years; were taking a SSRI or a SNRI antidepressant for at least 6 weeks at an adequate dose; scored ≥ 14 points on the Beck Depression Inventory-II (BDI-II); were adherent to medication; and met the International Statistical Classification of Diseases and Related Health Problems, Tenth Revision, criteria for depression.

INTERVENTIONS

Participants were randomised using a computer-generated code to either oral mirtazapine or a matched placebo, starting at a dose of 15 mg daily for 2 weeks and increasing to 30 mg daily for up to 12 months, in addition to their usual antidepressant. Participants, their general practitioners (GPs) and the research team were blind to the allocation.

MAIN OUTCOME MEASURES

The primary outcome was depression symptoms at 12 weeks post randomisation compared with baseline, measured as a continuous variable using the BDI-II. Secondary outcomes (at 12, 24 and 52 weeks) included response, remission of depression, change in anxiety symptoms, adverse events (AEs), quality of life, adherence to medication, health and social care use and cost-effectiveness. Outcomes were analysed on an intention-to-treat basis. A qualitative study explored patients' views and experiences of managing depression and GPs' views on prescribing a second antidepressant.

RESULTS

There were 480 patients randomised to the trial (mirtazapine and usual care, n = 241; placebo and usual care, n = 239), of whom 431 patients (89.8%) were followed up at 12 weeks. BDI-II scores at 12 weeks were lower in the mirtazapine group than the placebo group after adjustment for baseline BDI-II score and minimisation and stratification variables [difference -1.83 points, 95% confidence interval (CI) -3.92 to 0.27 points; p = 0.087]. This was smaller than the minimum clinically important difference and the CI included the null. The difference became smaller at subsequent time points (24 weeks: -0.85 points, 95% CI -3.12 to 1.43 points; 12 months: 0.17 points, 95% CI -2.13 to 2.46 points). More participants in the mirtazapine group withdrew from the trial medication, citing mild AEs (46 vs. 9 participants).

CONCLUSIONS

This study did not find convincing evidence of a clinically important benefit for mirtazapine in addition to a SSRI or a SNRI antidepressant over placebo in primary care patients with TRD. There was no evidence that the addition of mirtazapine was a cost-effective use of NHS resources. GPs and patients were concerned about adding an additional antidepressant.

LIMITATIONS

Voluntary unblinding for participants after the primary outcome at 12 weeks made interpretation of longer-term outcomes more difficult.

FUTURE WORK

Treatment-resistant depression remains an area of important, unmet need, with limited evidence of effective treatments. Promising interventions include augmentation with atypical antipsychotics and treatment using transcranial magnetic stimulation.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN06653773; EudraCT number 2012-000090-23.

FUNDING

This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 63. See the NIHR Journals Library website for further project information.

The COMET (Comparison of Operative versus Monitoring and Endocrine Therapy) trial: a phase III randomised controlled clinical trial for low-risk ductal carcinoma in situ (DCIS)

INTRODUCTION

Ductal carcinoma in situ (DCIS) is a non-invasive non-obligate precursor of invasive breast cancer. With guideline concordant care (GCC), DCIS outcomes are at least as favourable as some other early stage cancer types such as prostate cancer, for which active surveillance (AS) is a standard of care option. However, AS has not yet been tested in relation to DCIS. The goal of the COMET (Comparison of Operative versus Monitoring and Endocrine Therapy) trial for low-risk DCIS is to gather evidence to help future patients consider the range of treatment choices for low-risk DCIS, from standard therapies to AS. The trial will determine whether there may be some women who do not substantially benefit from current GCC and who could thus be safely managed with AS. This protocol is version 5 (11 July 2018). Any future protocol amendments will be submitted to Quorum Centralised Institutional Review Board/local institutional review boards for approval via the sponsor of the study (Alliance Foundation Trials).

METHODS AND ANALYSIS

COMET is a phase III, randomised controlled clinical trial for patients with low-risk DCIS. The primary outcome is ipsilateral invasive breast cancer rate in women undergoing GCC compared with AS. Secondary objectives will be to compare surgical, oncological and patient-reported outcomes. Patients randomised to the GCC group will undergo surgery as well as radiotherapy when appropriate; those in the AS group will be monitored closely with surgery only on identification of invasive breast cancer. Patients in both the GCC and AS groups will have the option of endocrine therapy. The total planned accrual goal is 1200 patients.

ETHICS AND DISSEMINATION

The COMET trial will be subject to biannual formal review at the Alliance Foundation Data Safety Monitoring Board meetings. Interim analyses for futility/safety will be completed annually, with reporting following Consolidated Standards of Reporting Trials (CONSORT) guidelines for non-inferiority trials.

TRIAL REGISTRATION NUMBER

NCT02926911; Pre-results.