Nonadherence to treatment protocol in published randomised controlled trials: a review

Feasibility of an < 24 h discharge pathway with tele-monitoring after elective colectomies: a pilot study

INTRODUCTION

Implementation of enhanced recovery after surgery principles has led to exploration of ambulatory pathways in surgery, including gastrointestinal surgery. However, implementation of ambulatory pathways after colorectal surgery has not been established yet. Previous studies suggest that discharge within 24 h in colorectal surgery is only possible with a clear protocol and careful patient selection.

METHODS

Single center prospective feasibility pilot study of thirty patients in one large non-academic teaching hospital in the Netherlands. Patients were included if they were between 18 and 80 years old, underwent elective minimal invasive colonic resection with anastomosis, had a ASA-score of I or II, fully understood the procedure, had a person at home the first 4 days after surgery and lived within 30 min travel radius to the hospital. Exclusion criteria were cT4 tumours, multi-visceral resections, insulin-dependent diabetes, anti-coagulants which required perioperative bridging, and perioperative complications. Patients followed a pathway with discharge within 24 h postoperatively and were monitored by a tele-monitoring smartphone application after discharge.

RESULTS

Thirty patients were included and twenty-one patients (70%) fulfilled discharge criteria within 24 h after surgery. Six (20%) patients were readmitted within 30 days. Complications occurred in six (20%) patients, which was classified as Clavien-Dindo ≥ 3 complication in one (3%) patient. Patients and health care provider satisfaction was high.

CONCLUSION

Findings of this study support the feasibility and safety of an early discharge protocol with tele-monitoring after minimal invasive colonic resection. Satisfaction of patients and health care providers was high.

General medication adherence scale in patients with chronic illnesses: Persian translation and psychometric evaluation

ObjectivesThis study was conducted with the aim of determining the validity and reliability of the Persian version of "General Medication Adherence Scale (GMAS)" in chronic patients in Iran.MethodologyThe study was conducted among patients with chronic diseases in five hospitals of Iran. In this study, after cultural validation, using the steps of Content, Response Reaction, and Internal structure evaluations, the research sample was increased to 150 individuals for exploratory factor analysis (EFA) and 313 chronic patients for confirmatory factor analysis (CFA) to confirm the construct validity. Cronbach's alpha coefficient was used to assess internal consistency, and test-retest method was used to evaluate the reliability of the tool.FindingsThe results of EFA and CFA confirmed the tool with three factors and 11 items. The R2 index in the above model was estimated at 0.99, indicating that 99% of the variation in medication adherence scores in research units was explained by GMAS with 11 items. The main indices of the model in factor analysis were all above 0.9, indicating a good fit for the model.DiscussionOverall, the study results showed that the Persian version of GMAS has acceptable and practical characteristics for evaluating medication adherence, and it can be used as a valid tool in various related fields.

Is inverse probability of censoring weighting a safer choice than per-protocol analysis in clinical trials?

Deviation from the treatment strategy under investigation occurs in many clinical trials. We term this intervention deviation. Per-protocol analyses are widely adopted to estimate a hypothetical estimand without the occurrence of intervention deviation. Per-protocol by censoring is prone to selection bias when intervention deviation is associated with time-varying confounders that also influence counterfactual outcomes. This can be corrected by inverse probability of censoring weighting, which gives extra weight to uncensored individuals who had similar prognostic characteristics to censored individuals. Such weights are computed by modelling selected covariates. Inverse probability of censoring weighting relies on the no unmeasured confounding assumption whose plausibility is not statistically testable. Suboptimal implementation of inverse probability of censoring weighting which violates the assumption will lead to bias. In a simulation study, we evaluated the performance of per-protocol and inverse probability of censoring weighting with different implementations to explore whether inverse probability of censoring weighting is a safe alternative to per-protocol. Scenarios were designed to vary intervention deviation in one or both arms with different prevalences, correlation between two confounders, effect of each confounder, and sample size. Results show that inverse probability of censoring weighting with different combinations of covariates outperforms per-protocol in most scenarios, except for an unusual case where selection bias caused by two confounders is in two directions, and 'cancels' out.

Methodological Challenges in Randomized Controlled Trials of mHealth Interventions: Cross-Sectional Survey Study and Consensus-Based Recommendations

BACKGROUND

Mobile health (mHealth) refers to using mobile communication devices such as smartphones to support health, health care, and public health. mHealth interventions have their own nature and characteristics that distinguish them from traditional health care interventions, including drug interventions. Thus, randomized controlled trials (RCTs) of mHealth interventions present specific methodological challenges. Identifying and overcoming those challenges is essential to determine whether mHealth interventions improve health outcomes.

OBJECTIVE

We aimed to identify specific methodological challenges in RCTs testing mHealth interventions' effects and develop consensus-based recommendations to address selected challenges.

METHODS

A 2-phase participatory research project was conducted. First, we sent a web-based survey to authors of mHealth RCTs. Survey respondents rated on a 5-point scale how challenging they found 21 methodological aspects in mHealth RCTs compared to non-mHealth RCTs. Nonsystematic searches until June 2022 informed the selection of the methodological challenges listed in the survey. Second, a subset of survey respondents participated in an online workshop to discuss recommendations to address selected methodological aspects identified in the survey. Finally, consensus-based recommendations were developed based on the workshop discussion and email interaction.

RESULTS

We contacted 1535 authors of mHealth intervention RCTs, of whom 80 (5.21%) completed the survey. Most respondents (74/80, 92%) identified at least one methodological aspect as more or much more challenging in mHealth RCTs. The aspects most frequently reported as more or much more challenging were those related to mHealth intervention integrity, that is, the degree to which the study intervention was implemented as intended, in particular managing low adherence to the mHealth intervention (43/77, 56%), defining adherence (39/79, 49%), measuring adherence (33/78, 42%), and determining which mHealth intervention components are used or received by the participant (31/75, 41%). Other challenges were also frequent, such as analyzing passive data (eg, data collected from smartphone sensors; 24/58, 41%) and verifying the participants' identity during recruitment (28/68, 41%). In total, 11 survey respondents participated in the subsequent workshop (n=8, 73% had been involved in at least 2 mHealth RCTs). We developed 17 consensus-based recommendations related to the following four categories: (1) how to measure adherence to the mHealth intervention (7 recommendations), (2) defining adequate adherence (2 recommendations), (3) dealing with low adherence rates (3 recommendations), and (4) addressing mHealth intervention components (5 recommendations).

CONCLUSIONS

RCTs of mHealth interventions have specific methodological challenges compared to those of non-mHealth interventions, particularly those related to intervention integrity. Following our recommendations for addressing these challenges can lead to more reliable assessments of the effects of mHealth interventions on health outcomes.

Extended versus Standard Proning Duration for COVID-19-associated Acute Respiratory Distress Syndrome: A Target Trial Emulation Study

Rationale: Prone positioning for ⩾16 hours in moderate-to-severe acute respiratory distress syndrome (ARDS) improves survival. However, the optimal duration of proning is unknown. Objectives: To estimate the effect of extended versus standard proning duration on patients with moderate-to-severe coronavirus disease (COVID-19) ARDS. Methods: Data were extracted from a five-hospital electronic medical record registry. Patients who were proned within 72 hours of mechanical ventilation were categorized as receiving extended (⩾24 h) versus standard (16-24 h) proning based on the first proning session length. We used a target trial emulation design to estimate the effect of extended versus standard proning on the primary outcome of 90-day mortality and secondary outcomes of ventilator liberation and intensive care unit (ICU) discharge. Analytically, we used inverse probability of treatment weighted (IPTW) Cox or Fine-Gray regression models. Results: A total of 314 patients were included; 234 received extended proning, and 80 received standard-duration proning. Patients who received extended proning were older, had greater comorbidity, were more often at an academic hospital, and had shorter time from admission to mechanical ventilation. After IPTW, characteristics were well balanced. Unadjusted 90-day mortality in the extended versus standard proning groups was 39% versus 58%. In doubly robust IPTW analyses, we found no significant effects of extended versus standard proning duration on mortality (hazard ratio [95% confidence interval], 0.95 [0.51-1.77]), ventilator liberation (subdistribution hazard, 1.60 [0.97-2.64], or ICU discharge (subdistribution hazard, 1.31 [0.82-2.10]). Conclusions: Using target trial emulation, we found no significant effect of extended versus standard proning duration on mortality, ventilator liberation, or ICU discharge. However, given the imprecision of estimates, further study is justified.

Scientific Committee guidance on appraising and integrating evidence from epidemiological studies for use in EFSA's scientific assessments

EFSA requested its Scientific Committee to prepare a guidance document on appraising and integrating evidence from epidemiological studies for use in EFSA's scientific assessments. The guidance document provides an introduction to epidemiological studies and illustrates the typical biases, which may be present in different epidemiological study designs. It then describes key epidemiological concepts relevant for evidence appraisal. This includes brief explanations for measures of association, exposure assessment, statistical inference, systematic error and effect modification. The guidance then describes the concept of external validity and the principles of appraising epidemiological studies. The customisation of the study appraisal process is explained including tailoring of tools for assessing the risk of bias (RoB). Several examples of appraising experimental and observational studies using a RoB tool are annexed to the document to illustrate the application of the approach. The latter part of this guidance focuses on different steps of evidence integration, first within and then across different streams of evidence. With respect to risk characterisation, the guidance considers how evidence from human epidemiological studies can be used in dose-response modelling with several different options being presented. Finally, the guidance addresses the application of uncertainty factors in risk characterisation when using evidence from human epidemiological studies.

Physician and patient adherence in hypertension trials: a point of view on an important issue to resolve

INTRODUCTION

Randomized controlled trials (RCTs) are important sources of evidence that strongly influence guidelines for patient management, including for elevated blood pressure in adults.

AREAS COVERED

Critical questions regarding the interpretation of hypertension trial results have recently increased, especially for concerns over methodology. In particular, investigator adherence to the protocol and patient adherence to investigational drugs are often far from optimal. These issues may be ignored or underreported because physicians' behavior during trials is often not monitored and patients' medication adherence is neither measured adequately nor reported or analyzed in the final report or in the publication. This situation may lead to misinterpretations of study results and misevaluations of the safety and efficacy profile of new drugs. In this short review, the problem of measuring, reporting, and analyzing drug adherence in RCTs is discussed and illustrated with several examples in the field of hypertension.

EXPERT OPINION

The main conclusion is that drug adherence should always be measured in clinical trials, possibly with more than one method. In addition, prespecified analyses of adherence data should be included in the statistical plan of all trials to improve their overall quality.

Assessing efficacy in non-inferiority trials with non-adherence to interventions: Are intention-to-treat and per-protocol analyses fit for purpose?

BACKGROUND

Non-inferiority trials comparing different active drugs are often subject to treatment non-adherence. Intention-to-treat (ITT) and per-protocol (PP) analyses have been advocated in such studies but are not guaranteed to be unbiased in the presence of differential non-adherence.

METHODS

The REMoxTB trial evaluated two 4-month experimental regimens compared with a 6-month control regimen for newly diagnosed drug-susceptible TB. The primary endpoint was a composite unfavorable outcome of treatment failure or recurrence within 18 months post-randomization. We conducted a simulation study based on REMoxTB to assess the performance of statistical methods for handling non-adherence in non-inferiority trials, including: ITT and PP analyses, adjustment for observed adherence, multiple imputation (MI) of outcomes, inverse-probability-of-treatment weighting (IPTW), and a doubly-robust (DR) estimator.

RESULTS

When non-adherence differed between trial arms, ITT, and PP analyses often resulted in non-trivial bias in the estimated treatment effect, which consequently under- or over-inflated the type I error rate. Adjustment for observed adherence led to similar issues, whereas the MI, IPTW and DR approaches were able to correct bias under most non-adherence scenarios; they could not always eliminate bias entirely in the presence of unobserved confounding. The IPTW and DR methods were generally unbiased and maintained desired type I error rates and statistical power.

CONCLUSIONS

When non-adherence differs between trial arms, ITT and PP analyses can produce biased estimates of efficacy, potentially leading to the acceptance of inferior treatments or efficacious regimens being missed. IPTW and the DR estimator are relatively straightforward methods to supplement ITT and PP approaches.

Nutrition and movement to improve quality of life in patients with knee osteoarthritis: the NUMOQUA study protocol for a randomised controlled trial

BACKGROUND

Osteoarthritis (OA) has long been considered as a degenerative disease of cartilage tissue resulting from bodily wear and tear. However, there is accumulating evidence that inflammation plays a key role in the pathogenesis of OA. In knee OA, the most common form of OA, exercise therapy as an effective component of early treatment addresses functional deficits, pain and inflammation. Since inflammation is critical for the development and progress of OA, anti-inflammatory therapies must be combined strategically. In the course of the NUMOQUA project, an anti-inflammatory therapeutic diet named 'Austrian Osteoarthritis Cuisine' was developed. It is based on the framework of the New Nordic Diet combined with the food-based dietary guidelines of Austria, the guidelines for OA, the Austrian food culture and the principles of a sustainable diet. The present study examines the implementation of the 'Austrian OA Cuisine' combined with the evidence-based training programme GLA:D® (Good Life with osteoArthritis in Denmark) in Austrian patients with knee OA and the effects on quality of life, nutritional and inflammatory status, as well as oxidative stress parameters.

METHODS

A total of 60 participants aged 50 to 75 with knee OA will be included and randomly assigned either to the intervention group or the control group. All participants will undergo the GLA:D® programme in the first 6 weeks. Additionally, the intervention group will receive nutritional group training and individual nutritional counselling on the 'Austrian OA Cuisine' over 9 months. The control group will receive general information about a healthy lifestyle. Measurements at baseline and at 4 follow-up dates include nutritional, inflammatory and oxidative stress markers. Furthermore, anthropometric, behavioural and clinical data will be obtained. The recruitment process lasted from autumn 2022 to January 2024, followed by the intervention until October 2024.

DISCUSSION

The prevalence of OA is expected to increase in the future due to ongoing demographic changes and rising obesity rates. The expected results will provide important evidence on whether this interdisciplinary therapeutic approach could be a new, cost-effective and sustainable strategy to address the disease process of OA without negative side effects.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05955300. Date of registration: 23rd of October 2023.

Pairwise comparisons of three medication adherence outcomes in adolescents who use alcohol

BACKGROUND

Accurate assessment of medication adherence is important for understanding pharmacotherapy outcomes across all phases of adolescent substance use disorder (SUD) clinical trials. The objective of this study was to describe and assess the pairwise concordance between three commonly used non-biological medication adherence assessment methods in adolescents who use alcohol to inform the selection of medication adherence measures for use in future youth SUD trials.

METHODS

Participants (N = 32, 17-19-years-old) took N-acetylcysteine and placebo, in a randomized cross-over design, for 10 days each. Medication adherence was assessed (20 days total) via pill count, medication videos submitted twice daily, and the Medication Event Monitoring System (MEMS®). Lin's Concordance Correlation Coefficient (CCC) assessed concordance and Bland-Altman plots are reported. Linear mixed-effects models with main effects of medication, treatment block (first medication, second medication), and sequence were also run.

RESULTS

Medication videos yielded the lowest (64%) and pill count yielded the highest (89%) adherence estimates. CCC values indicated poor correspondence, except between pill count and MEMS. The Bland-Altman plots showed good pairwise agreement between all methods. Linear mixed-effects models indicated a difference between the first and second cross-over medication, with adherence estimates being lower for the second medication, regardless of whether it was N-acetylcysteine or placebo.

CONCLUSIONS

The study yielded important and practical information. First, incorporating more than one method of adherence assessment may capture estimated floor and ceiling adherence in the absence of a biological marker. This is particularly relevant for remote or hybrid studies where bio-marker collection is challenging. Selection of the assessment methods will depend on study goals. Second, the continuation of medication adherence research can benefit each phase of clinical trials and inform rigorous pharmacotherapy evaluation.

Assessing treatment adherence is crucial to determine adequacy of mineralocorticoid therapy

Background

There is no consensus strategy for mineralocorticoid (MC) therapy titration in patients with primary adrenal insufficiency (PAI). We aim to measure serum fludrocortisone (sFC) and urine fludrocortisone (uFC) levels and to determine their utility, alongside clinical/biochemical variables and treatment adherence to guide MC replacement dose titration.

Methods

Multi-centre, observational, cross-sectional study on 41 patients with PAI on MC replacement therapy. sFC and uFC levels (measured by liquid chromatography-tandem mass spectrometry), plasma renin concentration (PRC), electrolytes (Na+, K+), mean arterial blood pressure (MAP), total daily glucocorticoid (dGC) and MC (dMC) dose, and assessment of treatment adherence were incorporated into statistical models.

Results

We observed a close relationship between sFC and uFC (r = 0.434, P = 0.005) and between sFC and the time from the last fludrocortisone dose (r = -0.355, P = 0.023). Total dMC dose was related to dGC dose (r = 0.556, P < 0.001), K+ (r = -0.388, P = 0.013) as well as sFC (r = 0.356, P = 0.022) and uFC (r = 0.531, P < 0.001). PRC was related to Na+ (r = 0.517, P < 0.001) and MAP (r = -0.427, P = 0.006), but not to MC dose, sFC or uFC. Regression analyses did not support a role for sFC, uFC or PRC measurements and confirmed K+ (B = -44.593, P = 0.005) as the most important variable to guide dMC titration. Of the patients, 32% were non-adherent with replacement therapy. When adherence was inserted into the regression model, it was the only factor affecting dMC.

Conclusions

sFC and uFC levels are not helpful in guiding dMC titration. Treatment adherence impacts on clinical variables used to assess MC replacement and should be included as part of routine care in patients with PAI.

Starting a conversation about estimands with public partners involved in clinical trials: a co-developed tool

BACKGROUND

Clinical trials aim to draw conclusions about the effects of treatments, but a trial can address many different potential questions. For example, does the treatment work well for patients who take it as prescribed? Or does it work regardless of whether patients take it exactly as prescribed? Since different questions can lead to different conclusions on treatment benefit, it is important to clearly understand what treatment effect a trial aims to investigate-this is called the 'estimand'. Using estimands helps to ensure trials are designed and analysed to answer the questions of interest to different stakeholders, including patients and public. However, there is uncertainty about whether patients and public would like to be involved in defining estimands and how to do so. Public partners are patients and/or members of the public who are part of, or advise, the research team. We aimed to (i) co-develop a tool with public partners that helps explain what an estimand is and (ii) explore public partner's perspectives on the importance of discussing estimands during trial design.

METHODS

An online consultation meeting was held with 5 public partners of mixed age, gender and ethnicities, from various regions of the UK. Public partner opinions were collected and a practical tool describing estimands, drafted before the meeting by the research team, was developed. Afterwards, the tool was refined, and additional feedback sought via email.

RESULTS

Public partners want to be involved in estimand discussions. They found an introductory tool, to be presented and described to them by a researcher, helpful for starting a discussion about estimands in a trial design context. They recommended storytelling, analogies and visual aids within the tool. Four topics related to public partners' involvement in defining estimands were identified: (i) the importance of addressing questions that are relevant to patients and public in trials, (ii) involving public partners early on, (iii) a need for education and communication for all stakeholders and (iv) public partners and researchers working together.

CONCLUSIONS

We co-developed a tool for researchers and public partners to use to facilitate the involvement of public partners in estimand discussions.

Using modified intention-to-treat as a principal stratum estimator for failure to initiate treatment

BACKGROUND

A common intercurrent event affecting many trials is when some participants do not begin their assigned treatment. For example, in a double-blind drug trial, some participants may not receive any dose of study medication. Many trials use a 'modified intention-to-treat' approach, whereby participants who do not initiate treatment are excluded from the analysis. However, it is not clear (a) the estimand being targeted by such an approach and (b) the assumptions necessary for such an approach to be unbiased.

METHODS

Using potential outcome notation, we demonstrate that a modified intention-to-treat analysis which excludes participants who do not begin treatment is estimating a principal stratum estimand (i.e. the treatment effect in the subpopulation of participants who would begin treatment, regardless of which arm they were assigned to). The modified intention-to-treat estimator is unbiased for the principal stratum estimand under the assumption that the intercurrent event is not affected by the assigned treatment arm, that is, participants who initiate treatment in one arm would also do so in the other arm (i.e. if someone began the intervention, they would also have begun the control, and vice versa).

RESULTS

We identify two key criteria in determining whether the modified intention-to-treat estimator is likely to be unbiased: first, we must be able to measure the participants in each treatment arm who experience the intercurrent event, and second, the assumption that treatment allocation will not affect whether the participant begins treatment must be reasonable. Most double-blind trials will satisfy these criteria, as the decision to start treatment cannot be influenced by the allocation, and we provide an example of an open-label trial where these criteria are likely to be satisfied as well, implying that a modified intention-to-treat analysis which excludes participants who do not begin treatment is an unbiased estimator for the principal stratum effect in these settings. We also give two examples where these criteria will not be satisfied (one comparing an active intervention vs usual care, where we cannot identify which usual care participants would have initiated the active intervention, and another comparing two active interventions in an unblinded manner, where knowledge of the assigned treatment arm may affect the participant's choice to begin or not), implying that a modified intention-to-treat estimator will be biased in these settings.

CONCLUSION

A modified intention-to-treat analysis which excludes participants who do not begin treatment can be an unbiased estimator for the principal stratum estimand. Our framework can help identify when the assumptions for unbiasedness are likely to hold, and thus whether modified intention-to-treat is appropriate or not.

Strategies to Improve Adherence to Skin Self-examination and Other Self-management Practices in People at High Risk of Melanoma: A Scoping Review of Randomized Clinical Trials

Importance

Adherence, both in research trials and in clinical practice, is crucial to the success of interventions. There is limited guidance on strategies to increase adherence and the measurement and reporting of adherence in trials of melanoma self-management practices.

Objective

This scoping review aimed to describe (1) strategies to improve adherence to self-management practices in randomized clinical trials of people at high risk of melanoma and (2) measurement and reporting of adherence data in these trials.

Evidence Review

Four databases, including MEDLINE, Embase, CENTRAL, and CINAHL, were searched from inception to July 2022. Eligible studies were randomized clinical trials of self-monitoring interventions for early detection of melanoma in people at increased risk due to personal history (eg, melanoma, transplant, dysplastic naevus syndrome), family history of melanoma, or as determined by a risk assessment tool or clinical judgment.

Findings

From 939 records screened, 18 eligible randomized clinical trials were identified, ranging in size from 40 to 724 participants, using a range of adherence strategies but with sparse evidence on effectiveness of the strategies. Strategies were classified as trial design (n = 15); social and economic support (n = 5); intervention design (n = 18); intervention and condition support (n = 10); and participant support (n = 18). No strategies were reported for supporting underserved groups (eg, people who are socioeconomically disadvantaged, have low health literacy, non-English speakers, or older adults) to adhere to self-monitoring practices, and few trials targeted provider (referring to both clinicians and researchers) adherence (n = 5). Behavioral support tools included reminders (n = 8), priority-setting guidance (n = 5), and clinician feedback (n = 5). Measurement of adherence was usually by participant report of skin self-examination practice with some recent trials of digital interventions also directly measuring adherence to the intervention through website or application analytic data. Reporting of adherence data was limited, and fewer than half of all reports mentioned adherence in their discussion.

Conclusions and Relevance

Using an adaptation of the World Health Organization framework for clinical adherence, this scoping review of randomized clinical trials identified key concepts as well as gaps in the way adherence is approached in design, conduct, and reporting of trials for skin self-examination and other self-management practices in people at high risk of melanoma. These findings may usefully guide future trials and clinical practice; evaluation of adherence strategies may be possible using a Study Within A Trial (SWAT) framework within host trials.

The Emergency Medical Services Sleep Health Study: A cluster-randomized trial

BACKGROUND

Greater than half of emergency medical services (EMS) clinician shift workers report poor sleep, fatigue, and inadequate recovery between shifts. We hypothesized that EMS clinicians randomized to receive tailored sleep health education would have improved sleep quality and less fatigue compared to wait-list controls after 3 months.

METHODS

We used a cluster-randomized, 2-arm, wait-list control study design (clinicaltrials.gov identifier: NCT04218279). Recruitment of EMS agencies (clusters) was nationwide. Our study was powered at 88% to detect a 0.4 standard deviation difference in sleep quality with 20 agencies per arm and a minimum of 10 individuals per agency. The primary outcome was measured using the Pittsburgh Sleep Quality Index (PSQI) at 3-month follow-up. Our intervention was accessible in an online, asynchronous format and comprised of 10 brief education modules that address fatigue mitigation topics prescribed by the American College of Occupational Environmental Medicine.

RESULTS

In total, 36 EMS agencies and 678 individuals enrolled. Attrition at 3 months did not differ by study group (Intervention = 17.4% vs. Wait-list control = 18.2%; p = .37). Intention-to-treat analyses detected no differences in PSQI and fatigue scores at 3 months. Per protocol analyses showed the greater the number of education modules viewed, the greater the improvement in sleep quality and the greater the reduction in fatigue (p < .05).

CONCLUSIONS

While intention-to-treat analyses revealed no differences in sleep quality or fatigue at 3 months, per protocol findings identified select groups of EMS clinician shift workers who may benefit from sleep health education. Our findings may inform fatigue risk management programs.

Statistical methods for handling compliance in randomized controlled trials of device interventions: a systematic review

OBJECTIVES

We aimed to review the extent to which analysis of randomized controlled trials (RCTs) of device interventions includes methods to handle compliance to the study intervention as described in the protocol.

STUDY DESIGN AND SETTING

We conducted a systematic review of the statistical methods used to handle compliance to a device intervention when estimating the effect of the device compared to another intervention in RCTs. We searched Embase, MEDLINE, PsychInfo, and the Cochrane Central Register of Controlled Trials. We sought to evaluate what methods were used and how using these methods impacted the estimate of the effect size.

RESULTS

One hundred fifty eight RCTs were identified for inclusion, of which only 21 (13%) described using a method to account for compliance to the device intervention, consisting of alternative analysis populations such as per-protocol, modified intention-to-treat, or as-treated, alongside a primary intention-to-treat analysis. No causal inference methods were used. Fourteen (9%) studies included compliance as a factor in the analysis and investigated its effect on outcomes.

CONCLUSION

Although some studies consider methods to handle compliance, causal inference methods have not been well adopted in the analysis of device trials. An increased awareness of the applications of statistical methods to adjust for compliance is needed.

Academic and Community ICUs Participating in a Critical Care Randomized Trial: A Comparison of Patient Characteristics and Trial Metrics

Clinical research in Canada is conducted primarily in "academic" hospitals, whereas most clinical care is provided in "community" hospitals. The objective of this nested observational study was to compare patient characteristics, outcomes, process-of-care variables, and trial metrics for patients enrolled in a large randomized controlled trial who were admitted to academic and community hospitals in Canada.

DESIGN

We conducted a preplanned observational study nested within the Probiotics: Prevention of Severe Pneumonia and Endotracheal Colonization Trial (PROSPECT, a randomized controlled trial comparing probiotics to placebo in mechanically ventilated patients) Research Program.

SETTING

ICUs.

PATIENTS

Mechanically ventilated patients.

MEASUREMENTS

We compared patient characteristics, interventions, outcomes, and trial metrics between patients enrolled in PROSPECT from academic and community hospitals.

MAIN RESULTS

Participating centers included 34 (82.9%) academic and seven (17.1%) community hospitals, which enrolled 2,203 (86.2%) and 352 (13.8%) patients, respectively. Compared with academic hospitals, patients enrolled in community hospitals were older (mean [sd] 62.7 yr [14.9 yr] vs 59.5 yr [16.4 yr]; p = 0.044), had longer ICU stays (median [interquartile range {IQR}], 13 d [8-23 d] vs 11 d [7-8 d]; p = 0.012) and higher mortality (percentage, [95% CI] in the ICU, 30.4% [25.8-35.4%]vs 20.5% [18.9-11.3%]; p = 0.002) and hospital (40.6% [35.6-45.8%] vs 26.1% [24.3-27.9%]; p < 0.001). Trial metrics, including informed consent rate (85.9% vs 76.3%; p = 0.149), mean (sd) monthly enrolment rate (2.1 [1.4] vs 1.1 [0.7]; p = 0.119), and protocol adherence (90.6% vs 91.6%; p = 0.207), were similar between community and academic ICUs.

CONCLUSIONS

Community hospitals can conduct high-quality research, with similar trial metrics to academic hospitals. Patient characteristics differed between community and academic hospitals, highlighting the need for broader engagement of community hospitals in clinical research to ensure generalizability of study results.

Performance, Detection, Contamination, Compliance, and Cointervention Biases in Rehabilitation Research: What Are They and How Can They Affect the Results of Randomized Controlled Trials? Basic Information for Junior Researchers and Clinicians

ABSTRACT

Bias is a systematic error that can cause distorted results leading to incorrect conclusions. Intervention bias (i.e., contamination bias, cointervention bias, compliance bias, and performance bias) and detection bias are the most common biases in rehabilitation research. A better understanding of these biases is essential at all stages of research to enhance the quality of evidence in rehabilitation trials. Therefore, this narrative review aims to provide insights to the readers, clinicians, and researchers about contamination, cointervention, compliance, performance, and detection biases and ways of recognizing and mitigating them. The literature selected for this review was obtained mainly by compiling the information from several reviews looking at biases in rehabilitation. In addition, separate searches by biases and looking at reference lists of selected studies as well as using Scopus forward citation for relevant references were used.This review provides several strategies to guard against the impact of bias on study results. Clinicians, researchers, and other stakeholders are encouraged to apply these recommendations when designing and conducting rehabilitation trials.

The value of adherence information during clinical pharmaceutical trials

BACKGROUND/AIMS

The quality of the evidence used to evaluate a drug's safety and efficacy depends, in part, on how well participants adhere to the prescribed drug-taking regime. There are multiple approaches to measure adherence in clinical trials, varying in their cost and accuracy. We demonstrate a method for evaluating the cost-effectiveness of common adherence monitoring methods, considering the costs and data quality for drugs that differ in how forgiving they are of nonadherence.

METHODS

We propose a simulation approach to estimate the value of evidence about adherence, considering both costs of collection and potential errors in interpreting clinical trial results. We demonstrate the approach with a simulated clinical trial of nitrendipine, a common calcium channel blocker. We consider two trial designs, one using pretrial adherence to "enrich" the trial sample and one without an enrichment strategy. We use scenarios combining high and low values of two key properties of a clinical trial: participant adherence and drug forgiveness.

RESULTS

Under the conditions of these simulations, the most cost-effective adherence monitoring approach depends on both trial participant adherence and drug forgiveness. For example, the enrichment strategy is not cost-effective for the base scenario (high forgiveness and high adherence), but is for other scenarios. We also estimate the effects of evaluable patient analysis, a controversial procedure that excludes nonadherent participants from the analyses, after a trial is completed.

CONCLUSIONS

Our proposed approach can guide drug regulators and developers in designing efficient clinical trials and assessing the impact of nonadherence on trial results. It can identify cost-effective adherence-monitoring methods, given available knowledge about the methods, drug, and patients' expected adherence.

A novel peripheral biomarker for depression and antidepressant response

In contrast to healthy controls, the heterotrimeric G protein, Gsalpha (Gsα) is ensconced predominantly in lipid rafts in subjects with major depressive disorder (MDD) resulting in impaired stimulation of adenylyl cyclase. In this small proof-of-concept study, we examined the hypothesis that translocation of Gsα from lipid rafts toward a more facile activation of adenylyl cyclase is a biomarker for clinical response to antidepressants. There were 49 subjects with MDD (HamD₁₇ score ≥15) and 59 healthy controls at the screen visit. The AlphaScreen (PerkinElmer) assay measured both basal activity and prostaglandin E1 (PGE1) stimulation of Gsα-adenylyl cyclase to assess the extent of coupling of Gsα with adenylyl cyclase. At screen, platelet samples obtained from MDD subjects revealed significantly lower PGE1 activation of adenylyl cyclase activity than controls (p = 0.02). Subsequently, 19 consenting MDD subjects completed a 6-week open label antidepressant treatment trial. The 11 antidepressant responders (HamD₁₇ improvement ≥50% from screen) revealed significant increase in PGE1-stimulated adenylyl cyclase compared to non-responders (p = 0.05) with an effect size of 0.83 for the PGE1/Gsα lipid-raft biomarker. PGE1 stimulation increased by ≥30% from screen assessment in eight responders (72.7%) and two non-responders (25.0%) [Fisher exact = 0.07] with a positive predictive value for response of 80.0%. In this small, pilot study, increased PGE1 stimulated adenylyl cyclase was associated with antidepressant response in MDD subjects. These data suggest that a simple, high-throughput-capable assay for depression and antidepressant response can be developed. Future studies are needed to evaluate the utility of this biomarker for the treatment of MDD.

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.

Methylphenidate augmentation of escitalopram to enhance adherence to antidepressant treatment: a pilot randomized controlled trial

BACKGROUND

Adherence to treatment, i.e. the extent to which a patient's therapeutic engagement coincides with the prescribed treatment, is among the most important problems in mental health care. The current study investigated the influence of pairing an acute positive reinforcing dopaminergic/noradrenergic effect (methylphenidate, MPH) with a standard antidepressant on the rates of adherence to medication treatment. The primary objective of this study was to determine whether MPH + escitalopram resulted in higher rates of medication adherence relative to placebo + escitalopram.

METHODS

Twenty participants with moderate to severe depression were 1-1 randomized to either (1) 5 mg MPH + 10 mg escitalopram or (2) placebo + 10 mg escitalopram with the possibility for a dose increase at 4 weeks. A Bayesian analysis was conducted to evaluate the outcomes.

RESULTS

First, neither percent Pill count nor Medication Electronic Monitoring System adherence showed that MPH was superior to placebo. In fact, placebo showed slightly higher adherence rates on the primary (7.82% better than MPH) and secondary (7.07% better than MPH) outcomes. There was a less than 25% chance of MPH augmentation showing at least as good or better adherence than placebo. Second, both groups showed a significant effect of treatment on the QIDS-SR with a median effect of an 8.6-point score reduction. Third, neither subjective measures of adherence attitudes nor socio-demographic covariates had a significant influence on the primary or secondary outcome variables.

CONCLUSIONS

These data do not support the use of MPH to increase adherence to antidepressant medication in individuals with moderate to severe depression. CLINICALTRIALS.

GOV IDENTIFIER

NCT03388164 , registered on 01/02/2018.

Effectiveness of the Wearable Sensor based Ambient Intelligent Geriatric Management System (AmbIGeM) in Preventing Falls in Older People in Hospitals

Background

The Ambient Intelligent Geriatric Management (AmbIGeM) system augments best practice and involves a novel wearable sensor (accelerometer and gyroscope) worn by patients where the data captured by the sensor are interpreted by algorithms to trigger alerts on clinician handheld mobile devices when risk movements are detected.

Methods

A 3-cluster stepped-wedge pragmatic trial investigating the effect on the primary outcome of falls rate and secondary outcome of injurious fall and proportion of fallers. Three wards across 2 states were included. Patients aged ≥65 years were eligible. Patients requiring palliative care were excluded. The trial was registered with the Australia and New Zealand Clinical Trials registry, number 12617000981325.

Results

A total of 4924 older patients were admitted to the study wards with 1076 excluded and 3240 (1995 control, 1245 intervention) enrolled. The median proportion of study duration with valid readings per patient was 49% ((interquartile range [IQR] 25%-67%)). There was no significant difference between intervention and control relating to the falls rate (adjusted rate ratio = 1.41, 95% confidence interval [0.85, 2.34]; p = .192), proportion of fallers (odds ratio = 1.54, 95% confidence interval [0.91, 2.61]; p = .105), and injurious falls rate (adjusted rate ratio = 0.90, 95% confidence interval [0.38, 2.14]; p = .807). In a post hoc analysis, falls and injurious falls rate were reduced in the Geriatric Evaluation and Management Unit wards when the intervention period was compared to the control period.

Conclusions

The AmbIGeM system did not reduce the rate of falls, rate of injurious falls, or proportion of fallers. There remains a case for further exploration and refinement of this technology given the post hoc analysis findings with the Geriatric Evaluation and Management Unit wards.

Clinical Trials Registration Number: 12617000981325

Incorporating partial adherence into the principal stratification analysis framework

Participants in pragmatic clinical trials often partially adhere to treatment. However, to simplify the analysis, most studies dichotomize adherence (supposing that subjects received either full or no treatment), which can introduce biases in the results. For example, the popular approach of principal stratification is based on the concept that the population can be separated into strata based on how they will react to treatment assignment, but this framework does not include strata in which a partially adhering participant would belong. We expanded the principal stratification framework to allow partial adherers to have their own principal stratum and treatment level. The expanded approach is feasible in pragmatic settings. We have designed a Monte Carlo posterior sampling method to obtain the relevant parameter estimates. Simulations were completed under a range of settings where participants partially adhered to treatment, including a hypothetical setting from a published simulation trial on the topic of partial adherence. The inference method is additionally applied to data from a real randomized clinical trial that features partial adherence. Comparison of the simulation results indicated that our method is superior in most cases to the biased estimators obtained through standard principal stratification. Simulation results further suggest that our proposed method may lead to increased accuracy of inference in settings where study participants only partially adhere to assigned treatment.

Reducing Events of Noncompliance in Neurology Human Subjects Research: the Effect of Human Subjects Research Protection Training and Site Initiation Visits

In an effort to minimize protocol noncompliance in neurological research studies that can potentially compromise patient safety, delay completion of the study, and result in premature termination and added costs, we determined the effect of investigator trainings and site initiation visits (SIVs) on the occurrence of noncompliance events. Results of protocol audits conducted at the National Institute of Neurological Disorders and Stroke from 2003 to 2019 on 97 research protocols were retrospectively analyzed. Based on the depth of auditing and provision of investigator research training, audit data were separated into four arms: 1) Early Period, 2003 to 2012; 2) Middle Period, 2013 to 2016; and Late Period, 2017 to 2019, further divided into 3) Late Period without SIVs; and 4) Late Period with SIVs. Events of noncompliance were classified by the type of protocol deviation, the category, and the cause. In total, 952 events occurred across 1080 participants. Protocols audited during the Middle Period, compared to the Early Period, showed a decrease in the percentage of protocols with at least 1 noncompliance event. Protocols with SIVs had a further decrease in major, minor, procedural, eligibility, and policy events. Additionally, protocols audited during the Early Period had on average 0.46 major deviations per participant, compared to 0.26 events in protocols audited during the Middle Period, and 0.08 events in protocols audited during the Late Period with SIVs. Protocol deviations and noncompliance events in neurological clinical trials can be reduced by targeted investigator trainings and SIVs. These measures have major impacts on the integrity, safety, and effectiveness of human subjects research in neurology.

A randomised controlled feasibility trial to evaluate Lawsonia inermis (henna)'s effect on palmar-plantar erythrodysesthesia induced by capecitabine or pegylated liposomal doxorubicin

PURPOSE

To test the effectiveness of henna in the management of palmar-plantar erythrodysesthesia (PPE) in patients receiving treatment with capecitabine or pegylated liposomal doxorubicin (PLD).

METHOD

This was a randomized controlled feasibility study in three specialized tertiary cancer centers with 56 patients with a PPE grade 1 or above and various cancer diagnoses. The intervention included the local application of henna to the affected areas. The control group followed the same process with a henna inert. Primary outcome was PPE grade and secondary outcomes were the EORTC QLQ-C30, PPE-related QoL (HFS-14), activities of daily living (ECOG) and pain. Patients in both groups were assessed at baseline and then weekly at four follow-ups.

RESULTS

PPE grade in the intervention group (1-3.8%) was lower compared to the control group (4-13.38%) and also lower levels of pain were reported by the patients in the intervention group (2.46 ± 1.17) compared to the control (5.57 ± 2.01). ECOG status in the intervention group was improved compared to the control (p = 0.039). The intervention group, experienced higher Global Health Status (p ≤ 0.008), Physical function (p ≤ 0.001), Emotional Function (p = 0.029), Social function (p ≤ 0.001) and lower Fatigue (p ≤ 0.001) and Pain (p ≤ 0.001) compared to the Control group. A statistically significant interaction was found between Group and Time over the weekly measurements of HFS-14 scores (F = 5,009, p ≤ 0.002) indicating the significant effect of the intervention throughout the weekly assessments.

CONCLUSION

The trial provided preliminary evidence on henna's effectiveness for treating PPE during treatment with capecitabine or PLD, with lower PPE grades, better performance status and better HRQoL observed in the henna group. CLINICALTRIALS.

GOV IDENTIFIER

NCT01751893.

Defining and Identifying Per-protocol Effects in Randomized Trials

In trials with noncompliance to assigned treatment, researchers might be interested in estimating a per-protocol effect-a comparison of two counterfactual outcomes defined by treatment assignment and (often time-varying) compliance with a well-defined treatment protocol. Here, we provide a general counterfactual definition of a per-protocol effect and discuss examples of per-protocol effects that are of either substantive or methodologic interest. In doing so, we seek to make more concrete what per-protocol effects are and highlight that one can estimate per-protocol effects that are more than just a comparison of always taking treatment in two distinct treatment arms. We then discuss one set of identifiability conditions that allow for identification of a causal per-protocol effect, highlighting some potential violations of those conditions that might arise when estimating per-protocol effects.

Draft for internal testing Scientific Committee guidance on appraising and integrating evidence from epidemiological studies for use in EFSA's scientific assessments

EFSA requested its Scientific Committee to prepare a guidance document on appraising and integrating evidence from epidemiological studies for use in EFSA's scientific assessments. The guidance document provides an introduction to epidemiological studies and illustrates the typical biases of the different epidemiological study designs. It describes key epidemiological concepts relevant for evidence appraisal. Regarding study reliability, measures of association, exposure assessment, statistical inferences, systematic error and effect modification are explained. Regarding study relevance, the guidance describes the concept of external validity. The principles of appraising epidemiological studies are illustrated, and an overview of Risk of Bias (RoB) tools is given. A decision tree is developed to assist in the selection of the appropriate Risk of Bias tool, depending on study question, population and design. The customisation of the study appraisal process is explained, detailing the use of RoB tools and assessing the risk of bias in the body of evidence. Several examples of appraising experimental and observational studies using a Risk of Bias tool are annexed to the document to illustrate the application of the approach. This document constitutes a draft that will be applied in EFSA's assessments during a 1-year pilot phase and be revised and complemented as necessary. Before finalisation of the document, a public consultation will be launched.

Usage Metrics of Web-Based Interventions Evaluated in Randomized Controlled Trials: Systematic Review

Background

The evaluation of web-based interventions (defined as an intervention that can be downloaded or accessed on the internet through a web browser) in randomized controlled trials (RCTs) has increased over the past two decades. Little is known about how participants’ use of the intervention is measured, reported, and analyzed in these studies.

Objective

This study aimed to review the evaluation of web-based interventions in RCTs, assessing study characteristics and the methods used to record, and adjust for, intervention usage.

Methods

A systematic review of the literature was undertaken to identify all published reports of RCTs that involved a web-based intervention. A random sample of 100 published trials was selected for detailed data extraction. Information on trial characteristics was extracted, including whether web usage data were recorded, and if so, the methods used to gather these data and whether these data were used to inform efficacy analyses.

Results

A PubMed search identified 812 trials of web-based interventions published up to the end of 2017 and demonstrated a growing trend over time. Of the 100 studies reviewed, 90 studies collected web usage data, but more than half (49/90, 54%) of these studies did not state the method used for recording web usage. Only four studies attempted to check on the reliability of their web usage data collection methods. A total of 39% (35/90) studies reported patterns or levels of web intervention use, of which 21% (19/90) studies adjusted for intervention use in their outcome analysis, but only two of these used appropriate statistical methods.

Conclusions

Trialists frequently report a measure of web-based intervention usage but do not always report the collection method or provide enough detail on their analysis of web usage. Appropriate statistical methods to account for intervention use are rarely used and are not well reported even in the very few trials in which they are used. The number of trialists who attempt to check on the reliability of their web usage collection methods is extremely low.

Identification of factors important to study quality in exercise performance studies

OBJECTIVES

This study aimed to identify factors important to quality in exercise performance studies, specifically in the domains of aerobic, anaerobic and strength exercise. Factors related to diet and body composition were also targeted as these often influence or change with exercise.

DESIGN

Cross-sectional study employing focus groups and a modified Delphi method.

METHODS

Academic staff and research students within the discipline of exercise science in a research-intensive university participated in focus groups to generate discipline-specific factors important to study quality. These factors were subsequently presented in a modified Delphi survey to a panel of international researchers with expertise in at least one of the domains. Item consensus was defined as >70% agreement on importance. The initial round contained all items generated from the focus groups. Subsequent rounds only presented items where consensus was not achieved, and additional items suggested by participants.

RESULTS

The academic staff (n = 10) and research students (n = 9) generated 22 items generic to all exercise performance studies and 71 domain-specific items. Over two Delphi survey rounds involving 18 international researchers, consensus on importance was achieved for 19 generic items. Identified factors addressed exercise testing and prescription protocols, equipment and compliance to interventions. Consensus on 66 specific items was achieved but was limited by small domain-specific participant numbers (4-8).

CONCLUSIONS

Numerous discipline-specific factors were identified as important to study quality. These factors can subsequently be used to inform the development of a tool to evaluate study quality in exercise performance research or inform best clinical practice.

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.

Pregabalin alleviates clinical signs of syringomyelia-related central neuropathic pain in Cavalier King Charles Spaniel dogs: a randomized controlled trial

OBJECTIVE

We aimed to assess the efficacy and benefit-risk profile of pregabalin (PGN) to reduce the clinical signs of central neuropathic pain (CNeP) as reflected by scratching episodes in dogs with symptomatic syringomyelia (SM).

STUDY DESIGN

Randomized, double-blind, placebo-controlled crossover study.

ANIMALS

A total of 12 client-owned Cavalier King Charles Spaniels (age, 1.1-7.4 years, bodyweight, 8.2-10.8 kg) with magnetic resonance imaging-confirmed SM and clinical signs of CNeP.

METHODS

Dogs were randomized to either PGN 150 mg or placebo for 25 days, followed by 48 hour washout period before crossover to the alternate phase of 25 days. The primary outcome was defined as number of scratching events during 10 minutes of video-recorded physical activity. Treatment effect was estimated using a generalized estimation equation model. Benefit-risk and quality of life assessments were obtained through owner interviews focusing on potential adverse events.

RESULTS

The treatment effect estimate was an 84% (95% confidence interval = 75-89%) reduction in mean number of scratching events relative to baseline compared with placebo (p < 0.0001). Owner-assessed satisfactory quality of life was status quo and rated as 'good' or 'could not be better' in six/11 dogs and improved in four/11 dogs. The most prevalent adverse events were increased appetite in nine/12 dogs and transient ataxia in nine/12 dogs. There was one dog withdrawn by the owner 7 days after crossover to PGN owing to persistent ataxia. No dogs needed rescue analgesia during the trial.

CONCLUSIONS AND CLINICAL RELEVANCE

PGN is superior to placebo in the reduction of clinical signs of SM-related CNeP in dogs. At a dose range of 13-19 mg kg^-1 orally twice daily, the encountered adverse events were acceptable to all but one owner.

The effects of medication adherence on study outcomes in randomized clinical trials: A role for cognitive dysfunction?

Medication nonadherence is common and has been associated with poor health outcomes. Older adults are especially likely to be non-adherent to their medications, as they often have more medications to manage and are at greater risk for cognitive dysfunction. Though less frequently examined, the association between cognitive dysfunction and nonadherence also likely extends to clinical trials research. The current study used archival data to examine the potential impact of cognitive dysfunction on adherence to a nutritional supplement as part of a 90-day randomized clinical trial in neurologically healthy middle-aged and older adults. Results showed overall cognitive performance was predictive of adherence to capsule intake when controlling for polypharmacy [F(1,157) = 6.53, p < .01]. These results suggest that cognitive dysfunction may impact findings from RCTs through its adverse impact on adherence to study protocol, possibly leading to greater treatment variance, artificially reduced treatment effects, lower study power, and distorted study outcomes and conclusions. A better understanding of methodological and statistical approaches to account for these unwanted effects are needed.

What are the statistical implications of treatment non-compliance in cluster randomized trials: A simulation study

Subjects in randomized controlled trials do not always comply to the treatment condition they have been assigned to. This may cause the estimated effect of the intervention to be biased and also affect efficiency, coverage of confidence intervals, and statistical power. In cluster randomized trials non‐compliance may occur at the subject level but also at the cluster level. In the latter case, all subjects within the same cluster have the same compliance status. The purpose of this study is to investigate the statistical implications of non‐compliance in cluster randomized trials. A simulation study was conducted with varying degrees of non‐compliance at either the cluster level or subject level. The probability of non‐compliance depends on a covariate at the cluster or subject level. Various realistic values of the intraclass correlation coefficient and cluster size are used. The data are analyzed by intention to treat, as treated, per protocol and the instrumental variable approach. The results show non‐compliance may result in downward biased estimates of the intervention effect and an under‐ or overestimate of its standard deviation. The coverage of the confidence intervals may be too small, and in most cases, empirical power is too small. The results are more severe when the probability of non‐compliance increases and the covariate that affects compliance is unobserved. It is advocated to avoid non‐compliance. If this is not possible, compliance status and covariates that affect compliance should be measured and included in the statistical model.

Local average treatment effects estimation via substantive model compatible multiple imputation

Nonadherence to assigned treatment is common in randomized controlled trials (RCTs). Recently, there has been increased interest in estimating causal effects of treatment received, for example, the so-called local average treatment effect (LATE). Instrumental variables (IV) methods can be used for identification, with estimation proceeding either via fully parametric mixture models or two-stage least squares (TSLS). TSLS is popular but can be problematic for binary outcomes where the estimand of interest is a causal odds ratio. Mixture models are rarely used in practice, perhaps because of their perceived complexity and need for specialist software. Here, we propose using multiple imputation (MI) to impute the latent compliance class appearing in the mixture models. Since such models include an interaction term between the latent compliance class and randomized treatment, we use "substantive model compatible" MI (SMC MIC), which can additionally handle missing data in outcomes and other variables in the model, before fitting the mixture models via maximum likelihood to the MI data sets and combining results via Rubin's rules. We use simulations to compare the performance of SMC MIC to existing approaches and also illustrate the methods by reanalyzing an RCT in UK primary health. We show that SMC MIC can be more efficient than full Bayesian estimation when auxiliary variables are incorporated, and is superior to two-stage methods, especially for binary outcomes.

Adjustment for treatment changes in epilepsy trials: A comparison of causal methods for time-to-event outcomes

BACKGROUND

When trials are subject to departures from randomised treatment, simple statistical methods that aim to estimate treatment efficacy, such as per protocol or as treated analyses, typically introduce selection bias. More appropriate methods to adjust for departure from randomised treatment are rarely employed, primarily due to their complexity and unfamiliarity. We demonstrate the use of causal methodologies for the production of estimands with valid causal interpretation for time-to-event outcomes in the analysis of a complex epilepsy trial, as an example to guide non-specialist analysts undertaking similar analyses.

METHODS

Two causal methods, the structural failure time model and inverse probability of censoring weighting, are adapted to allow for skewed time-varying confounders, competing reasons for treatment changes and a complicated time to remission outcome. We demonstrate the impact of various factors: choice of method (structural failure time model versus inverse probability of censoring weighting), model for inverse probability of censoring weighting (pooled logistic regression versus Cox models), time interval (for creating panel data for time-varying confounders and outcome), choice of confounders and (in pooled logistic regression) use of splines to estimate underlying risk.

RESULTS

The structural failure time model could adjust for switches between trial treatments but had limited ability to adjust for the other treatment changes that occurred in this epilepsy trial. Inverse probability of censoring weighting was able to adjust for all treatment changes and demonstrated very similar results with Cox and pooled logistic regression models. Accounting for increasing numbers of time-varying confounders and reasons for treatment change suggested a more pronounced advantage of the control treatment than that obtained using intention to treat.

CONCLUSIONS

In a complex trial featuring a remission outcome, underlying assumptions of the structural failure time model are likely to be violated, and inverse probability of censoring weighting may provide the most useful option, assuming availability of appropriate data and sufficient sample sizes. Recommendations are provided for analysts when considering which of these methods should be applied in a given trial setting.

Oral Agents: Challenges With Self-Administered Medication Adherence in Clinical Trials

BACKGROUND

In oral agent clinical trials, patients may not be adherent to self-administration of study medication; this nonadherence can affect validity and reliability. Many factors contribute to nonadherence to protocol requirements, and managing patients with fidelity issues is the responsibility of the research team.

OBJECTIVES

The aim is to identify which group (patients, physicians/principal investigators, nurses, or other personnel) research nurses report as most responsible for protocol nonadherence and to characterize the most observed causes and contributors to nonadherence within each group.

METHODS

Sixty-seven protocol nurses completed a nine-question survey developed from pilot data. Descriptive statistics and ordinal regressions addressed the objectives of the study.

FINDINGS

More than half of the nurses observed clinical trial nonadherence in their practices. Nurses identified challenges regarding physician, patient, and nurse factors. The most frequently identified causes included patients' forgetfulness, refusal to undergo study procedures, inadequate family or caregiver support to complete study activities, ineffective communication, and collaboration within the research team.

Reporting non-adherence in cluster randomised trials: A systematic review

BACKGROUND

Treatment non-adherence in randomised trials refers to situations where some participants do not receive their allocated treatment as intended. For cluster randomised trials, where the unit of randomisation is a group of participants, non-adherence may occur at the cluster or individual level. When non-adherence occurs, randomisation no longer guarantees that the relationship between treatment receipt and outcome is unconfounded, and the power to detect the treatment effects in intention-to-treat analysis may be reduced. Thus, recording adherence and estimating the causal treatment effect adequately are of interest for clinical trials.

OBJECTIVES

To assess the extent of reporting of non-adherence issues in published cluster trials and to establish which methods are currently being used for addressing non-adherence, if any, and whether clustering is accounted for in these.

METHODS

We systematically reviewed 132 cluster trials published in English in 2011 previously identified through a search in PubMed.

RESULTS

One-hundred and twenty three cluster trials were included in this systematic review. Non-adherence was reported in 56 cluster trials. Among these, 19 reported a treatment efficacy estimate: per protocol in 15 and as treated in 4. No study discussed the assumptions made by these methods, their plausibility or the sensitivity of the results to deviations from these assumptions.

LIMITATIONS

The year of publication of the cluster trials included in this review (2011) could be considered a limitation of this study; however, no new guidelines regarding the reporting and the handling of non-adherence for cluster trials have been published since. In addition, a single reviewer undertook the data extraction. To mitigate this, a second reviewer conducted a validation of the extraction process on 15 randomly selected reports. Agreement was satisfactory (93%).

CONCLUSION

Despite the recommendations of the Consolidated Standards of Reporting Trials statement extension to cluster randomised trials, treatment adherence is under-reported. Among the trials providing adherence information, there was substantial variation in how adherence was defined, handled and reported. Researchers should discuss the assumptions required for the results to be interpreted causally and whether these are scientifically plausible in their studies. Sensitivity analyses to study the robustness of the results to departures from these assumptions should be performed.

Methods for estimating complier average causal effects for cost-effectiveness analysis

In randomized controlled trials with treatment non-compliance, instrumental variable approaches are used to estimate complier average causal effects. We extend these approaches to cost-effectiveness analyses, where methods need to recognize the correlation between cost and health outcomes. We propose a Bayesian full likelihood approach, which jointly models the effects of random assignment on treatment received and the outcomes, and a three-stage least squares method, which acknowledges the correlation between the end points and the endogeneity of the treatment received. This investigation is motivated by the REFLUX study, which exemplifies the setting where compliance differs between the randomized controlled trial and routine practice. A simulation is used to compare the methods' performance. We find that failure to model the correlation between the outcomes and treatment received correctly can result in poor confidence interval coverage and biased estimates. By contrast, Bayesian full likelihood and three-stage least squares methods provide unbiased estimates with good coverage.

rpsftm: An R Package for Rank Preserving Structural Failure Time Models

Treatment switching in a randomised controlled trial occurs when participants change from their randomised treatment to the other trial treatment during the study. Failure to account for treatment switching in the analysis (i.e. by performing a standard intention-to-treat analysis) can lead to biased estimates of treatment efficacy. The rank preserving structural failure time model (RPSFTM) is a method used to adjust for treatment switching in trials with survival outcomes. The RPSFTM is due to Robins and Tsiatis (1991) and has been developed by White et al. (1997, 1999). The method is randomisation based and uses only the randomised treatment group, observed event times, and treatment history in order to estimate a causal treatment effect. The treatment effect, ψ, is estimated by balancing counter-factual event times (that would be observed if no treatment were received) between treatment groups. G-estimation is used to find the value of ψ such that a test statistic Z(ψ) = 0. This is usually the test statistic used in the intention-to-treat analysis, for example, the log rank test statistic. We present an R package that implements the method of rpsftm.

Multicenter Osteopathic Pneumonia Study in the Elderly: Subgroup Analysis on Hospital Length of Stay, Ventilator-Dependent Respiratory Failure Rate, and In-hospital Mortality Rate

CONTEXT

Osteopathic manipulative treatment (OMT) is a promising adjunctive treatment for older adults hospitalized for pneumonia.

OBJECTIVE

To report subgroup analyses from the Multicenter Osteopathic Pneumonia Study in the Elderly (MOPSE) relating to hospital length of stay (LOS), ventilator-dependent respiratory failure rate, and in-hospital mortality rate.

DESIGN

Multicenter randomized controlled trial.

SETTING

Seven community hospitals.

PARTICIPANTS

Three hundred eighty-seven patients aged 50 years or older who met specific criteria for pneumonia on hospital admission.

INTERVENTIONS

Participants were randomly assigned to 1 of 3 groups that received an adjunctive OMT protocol (n=130), a light touch (LT) protocol (n=124), or conventional care only (CCO) (n=133).

MAIN OUTCOME MEASURES

Outcomes for subgroup analyses were LOS, ventilator-dependent respiratory failure rate, and in-hospital mortality rate. Subgroups were age (50-74 years or ≥75 years), Pneumonia Severity Index (PSI) class (I-II, III, IV, or V), and type of pneumonia (community-acquired or nursing-home acquired). Data were analyzed by intention-to-treat and per-protocol analyses using stratified Cox proportional hazards models and Cochran-Mantel-Haenszel tests for general association.

RESULTS

By per-protocol analysis of the younger age subgroup, LOS was shorter for the OMT group (median, 2.9 days; n=43) than the LT (median, 3.7 days; n=45) and CCO (median, 4.0 days; n=65) groups (P=.006). By intention-to-treat analysis of the older age subgroup, in-hospital mortality rates were lower for the OMT (1 of 66 [2%]) and LT (2 of 68 [3%]) groups than the CCO group (9 of 67 [13%]) (P=.005). By per-protocol analysis of the PSI class IV subgroup, the OMT group had a shorter LOS than the CCO group (median, 3.8 days [n=40] vs 5.0 days [n=50]; P=.01) and a lower ventilator-dependent respiratory failure rate than the CCO group (0 of 40 [0%] vs 5 of 50 [10%]; P=.05). By intention-to-treat analysis, in-hospital mortality rates in the PSI class V subgroup were lower (P=.05) for the OMT group (1 of 22 [5%]) than the CCO group (6 of 19 [32%]) but not the LT group (2 of 15 [13%]).

CONCLUSION

Subgroup analyses suggested adjunctive OMT for pneumonia reduced LOS in adults aged 50 to 74 years and lowered in-hospital mortality rates in adults aged 75 years or older. Adjunctive OMT may also reduce LOS and in-hospital mortality rates in older adults with more severe pneumonia. Interestingly, LT also reduced in-hospital mortality rates in adults aged 75 years or older relative to CCO. (ClinicalTrials.gov number NCT00258661).

Lessons from the field: the conduct of randomized controlled trials in Botswana

Background

The conduct of randomized controlled trials (RCTs) in low-resource settings may present unique financial, logistic, and process-related challenges. Middle-income countries that have comparable disease burdens to low-income countries, but greater availability of resources, may be conducive settings for RCTs. Indeed, the country of Botswana is experiencing a rapid increase in the conduct of RCTs. Our objective was to explore the experiences of individuals conducting RCTs in Botswana to gain an understanding of the challenges and adaptive strategies to their work.

Methods

We conducted in-depth interviews with 14 national and international individuals working on RCTs in Botswana. Participants included principal investigators, research coordinators, lab technicians, research assistants, and other healthcare professionals. Interviews were audiotaped, transcribed verbatim, and coded for thematic analysis.

Results

Five primary themes were identified: ethics board relationships (including delays in the process); research staff management (including staff attrition and career development); study recruitment and retention (including the use of reimbursements); resource availability (including challenges accessing laboratory equipment); and capacity-building (including issues of exporting locally sourced samples). These themes were explored to discuss key challenges and adaptive strategies.

Conclusions

This study offers a first-hand account of individuals engaged in conducting RCTs in Botswana, a nation that is experiencing a rapid increase in research activities. Findings provide a foundational understanding for researchers in Botswana and trial managers in similar settings when planning RCTs so that the conduct of research does not outpace the ability to manage, support, and regulate it.

A framework for the design, conduct and interpretation of randomised controlled trials in the presence of treatment changes

BACKGROUND

When a randomised trial is subject to deviations from randomised treatment, analysis according to intention-to-treat does not estimate two important quantities: relative treatment efficacy and effectiveness in a setting different from that in the trial. Even in trials of a predominantly pragmatic nature, there may be numerous reasons to consider the extent, and impact on analysis, of such deviations from protocol. Simple methods such as per-protocol or as-treated analyses, which exclude or censor patients on the basis of their adherence, usually introduce selection and confounding biases. However, there exist appropriate causal estimation methods which seek to overcome these inherent biases, but these methods remain relatively unfamiliar and are rarely implemented in trials.

METHODS

This paper demonstrates when it may be of interest to look beyond intention-to-treat analysis for answers to alternative causal research questions through illustrative case studies. We seek to guide trialists on how to handle treatment changes in the design, conduct and planning the analysis of a trial; these changes may be planned or unplanned, and may or may not be permitted in the protocol. We highlight issues that must be considered at the trial planning stage relating to: the definition of nonadherence and the causal research question of interest, trial design, data collection, monitoring, statistical analysis and sample size.

RESULTS AND CONCLUSIONS

During trial planning, trialists should define their causal research questions of interest, anticipate the likely extent of treatment changes and use these to inform trial design, including the extent of data collection and data monitoring. A series of concise recommendations is presented to guide trialists when considering undertaking causal analyses.

Protocol adherence for continuously titrated interventions in randomized trials: an overview of the current methodology and case study

Background

The standard definition for protocol adherence is the proportion of all scheduled doses that are delivered. In clinical research, this definition has several limitations when evaluating protocol adherence in trials that study interventions requiring continuous titration.

Discussion

Building upon a specific case study, we analyzed a recent trial of a continuously titrated intervention to assess the impact of different definitions of protocol deviations on the interpretation of protocol adherence. The OVATION pilot trial was an open-label randomized controlled trial of higher (75–80 mmHg) versus lower (60–65 mmHg) mean arterial pressure (MAP) targets for vasopressor therapy in shock. In this trial, potential protocol deviations were defined as MAP values outside the targeted range for >4 consecutive hours during vasopressor therapy without synchronous and consistent adjustments of vasopressor doses. An adjudication committee reviewed each potential deviation to determine if it was clinically-justified or not. There are four reasons for this contextual measurement and reporting of protocol adherence. First, between-arm separation is a robust measure of adherence to complex protocols. Second, adherence assessed by protocol deviations varies in function of the definition of deviations and the frequency of measurements. Third, distinguishing clinically-justified vs. not clinically-justified protocol deviations acknowledges clinically sensible bedside decision-making and offers a clear terminology before the trial begins. Finally, multiple metrics exist to report protocol deviations, which provides different information but complementary information on protocol adherence.

Conclusions

In trials of interventions requiring continuous titration, metrics used for defining protocol deviations have a considerable impact on the interpretation of protocol adherence. Definitions for protocol deviations should be prespecified and correlated with between-arm separation, if it can be measured.

Electronic supplementary material

The online version of this article (doi:10.1186/s12874-017-0388-3) contains supplementary material, which is available to authorized users.