Design and analysis of clinical trials with clustering effects due to treatment

A randomized controlled trial of a Group psychological intervention to increase locus of control for alcohol consumption among Alcohol-Misusing Short-term (male) Prisoners (GASP)

BACKGROUND AND AIM

Reducing alcohol misuse by male prisoners is an important global issue. Control of drinking behaviour could be a useful target for intervention in this population, and locus of control could be a causal factor in this. We aimed to assess the effect of a clinical psychologist-facilitated group intervention on male prisoners' locus of control of drinking behaviour.

DESIGN

A two-arm, single-site, open, randomized controlled trial.

SETTING

A category B local training prison in South Wales, housing about 770 mainly sentenced men.

PARTICIPANTS

Prisoners serving less than 2 years who met inclusion criteria for pre-imprisonment alcohol misuse, alone or with drug misuse. A total of 119 were allocated to the intervention arm and 119 to the control arm; 104 and 87, respectively, completed the post-randomization baseline interview and 68 and 60 completed a second interview approximately 4 weeks later, respectively, after intervention or treatment as usual (TAU) alone.

INTERVENTION

Nine clinical psychologist-facilitated groups in the prison over 3 weeks. Range of participants per session was one to seven, with three to five most usual.

MEASURES

The primary outcome was locus of control of behaviour (LCB); secondary outcomes included mental state generally (comprehensive psychiatric rating scale/CPRS) and specifically (Beck Depression Inventory/BDI). An integral process evaluation was conducted.

FINDINGS

LCB scores decreased during the study, but without significant intervention effect [-1.7, 95% confidence interval (CI) = -5.1 to 1.6, P = 0.329]. Change among completers in the control group was from a mean score of 37.4 [standard deviation (SD) = 10.0] to 33.7[SD = 11.7] and in the intervention group from 37.4 (SD = 11.6) to 31.9 (SD = 11.8). Secondary outcomes, including change in mental state, did not differ between arms, but 686 (64%) sessions were lost, most because of 'prison issues'.

CONCLUSIONS

A clinical psychologist-facilitated group intervention did not have a statistically significant effect on sense of control of drinking behaviour among men with pre-imprisonment alcohol misuse serving less than 2 years in a South Wales prison. The study proved coterminous, however, with 40% prison staff cuts which seem likely to have contributed to the high loss of group sessions and possibly overwhelmed any treatment effect. Intervention completion failures, previously cited as harmful, had no effect here, so the trial should be repeated when the prison climate improves.

Robot-assisted training compared with an enhanced upper limb therapy programme and with usual care for upper limb functional limitation after stroke: the RATULS three-group RCT

BACKGROUND

Loss of arm function is common after stroke. Robot-assisted training may improve arm outcomes.

OBJECTIVE

The objectives were to determine the clinical effectiveness and cost-effectiveness of robot-assisted training, compared with an enhanced upper limb therapy programme and with usual care.

DESIGN

This was a pragmatic, observer-blind, multicentre randomised controlled trial with embedded health economic and process evaluations.

SETTING

The trial was set in four NHS trial centres.

PARTICIPANTS

Patients with moderate or severe upper limb functional limitation, between 1 week and 5 years following first stroke, were recruited.

INTERVENTIONS

Robot-assisted training using the Massachusetts Institute of Technology-Manus robotic gym system (InMotion commercial version, Interactive Motion Technologies, Inc., Watertown, MA, USA), an enhanced upper limb therapy programme comprising repetitive functional task practice, and usual care.

MAIN OUTCOME MEASURES

The primary outcome was upper limb functional recovery 'success' (assessed using the Action Research Arm Test) at 3 months. Secondary outcomes at 3 and 6 months were the Action Research Arm Test results, upper limb impairment (measured using the Fugl-Meyer Assessment), activities of daily living (measured using the Barthel Activities of Daily Living Index), quality of life (measured using the Stroke Impact Scale), resource use costs and quality-adjusted life-years.

RESULTS

A total of 770 participants were randomised (robot-assisted training, n = 257; enhanced upper limb therapy, n = 259; usual care, n = 254). Upper limb functional recovery 'success' was achieved in the robot-assisted training [103/232 (44%)], enhanced upper limb therapy [118/234 (50%)] and usual care groups [85/203 (42%)]. These differences were not statistically significant; the adjusted odds ratios were as follows: robot-assisted training versus usual care, 1.2 (98.33% confidence interval 0.7 to 2.0); enhanced upper limb therapy versus usual care, 1.5 (98.33% confidence interval 0.9 to 2.5); and robot-assisted training versus enhanced upper limb therapy, 0.8 (98.33% confidence interval 0.5 to 1.3). The robot-assisted training group had less upper limb impairment (as measured by the Fugl-Meyer Assessment motor subscale) than the usual care group at 3 and 6 months. The enhanced upper limb therapy group had less upper limb impairment (as measured by the Fugl-Meyer Assessment motor subscale), better mobility (as measured by the Stroke Impact Scale mobility domain) and better performance in activities of daily living (as measured by the Stroke Impact Scale activities of daily living domain) than the usual care group, at 3 months. The robot-assisted training group performed less well in activities of daily living (as measured by the Stroke Impact Scale activities of daily living domain) than the enhanced upper limb therapy group at 3 months. No other differences were clinically important and statistically significant. Participants found the robot-assisted training and the enhanced upper limb therapy group programmes acceptable. Neither intervention, as provided in this trial, was cost-effective at current National Institute for Health and Care Excellence willingness-to-pay thresholds for a quality-adjusted life-year.

CONCLUSIONS

Robot-assisted training did not improve upper limb function compared with usual care. Although robot-assisted training improved upper limb impairment, this did not translate into improvements in other outcomes. Enhanced upper limb therapy resulted in potentially important improvements on upper limb impairment, in performance of activities of daily living, and in mobility. Neither intervention was cost-effective.

FUTURE WORK

Further research is needed to find ways to translate the improvements in upper limb impairment seen with robot-assisted training into improvements in upper limb function and activities of daily living. Innovations to make rehabilitation programmes more cost-effective are required.

LIMITATIONS

Pragmatic inclusion criteria led to the recruitment of some participants with little prospect of recovery. The attrition rate was higher in the usual care group than in the robot-assisted training or enhanced upper limb therapy groups, and differential attrition is a potential source of bias. Obtaining accurate information about the usual care that participants were receiving was a challenge.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN69371850.

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. 54. See the NIHR Journals Library website for further project information.

A self-management programme to reduce falls and improve safe mobility in people with secondary progressive MS: the BRiMS feasibility RCT

BACKGROUND

Balance, mobility impairments and falls are common problems for people with multiple sclerosis (MS). Our ongoing research has led to the development of Balance Right in MS (BRiMS), a 13-week home- and group-based exercise and education programme intended to improve balance and encourage safer mobility.

OBJECTIVE

This feasibility trial aimed to obtain the necessary data and operational experience to finalise the planning of a future definitive multicentre randomised controlled trial.

DESIGN

Randomised controlled feasibility trial. Participants were block randomised 1 : 1. Researcher-blinded assessments were scheduled at baseline and at 15 and 27 weeks post randomisation. As is appropriate in a feasibility trial, statistical analyses were descriptive rather than involving formal/inferential comparisons. The qualitative elements utilised template analysis as the chosen analytical framework.

SETTING

Four sites across the UK.

PARTICIPANTS

Eligibility criteria included having a diagnosis of secondary progressive MS, an Expanded Disability Status Scale (EDSS) score of between ≥ 4.0 and ≤ 7.0 points and a self-report of two or more falls in the preceding 6 months.

INTERVENTIONS

Intervention - manualised 13-week education and exercise programme (BRiMS) plus usual care. Comparator - usual care alone.

MAIN OUTCOME MEASURES

Trial feasibility, proposed outcomes for the definitive trial (including impact of MS, mobility, quality of life and falls), feasibility of the BRiMS programme (via process evaluation) and economic data.

RESULTS

A total of 56 participants (mean age 59.7 years, standard deviation 9.7 years; 66% female; median EDSS score of 6.0 points, interquartile range 6.0-6.5 points) were recruited in 5 months; 30 were block randomised to the intervention group. The demographic and clinical data were broadly comparable at baseline; however, the intervention group scored worse on the majority of baseline outcome measures. Eleven participants (19.6%) withdrew or were lost to follow-up. Worsening of MS-related symptoms unrelated to the trial was the most common reason (n = 5) for withdrawal. Potential primary and secondary outcomes and economic data had completion rates of > 98% for all those assessed. However, the overall return rate for the patient-reported falls diary was 62%. After adjusting for baseline score, the differences between the groups (intervention compared with usual care) at week 27 for the potential primary outcomes were MS Walking Scale (12-item) version 2 -7.7 [95% confidence interval (CI) -17.2 to 1.8], MS Impact Scale (29-item) version 2 (MSIS-29vs2) physical 0.6 (95% CI -7.8 to 9) and MSIS-29vs2 psychological -0.4 (95% CI -9.9 to 9) (negative score indicates improvement). After the removal of one outlier, a total of 715 falls were self-reported over the 27-week trial period, with substantial variation between individuals (range 0-93 falls). Of these 715 falls, 101 (14%) were reported as injurious. Qualitative feedback indicated that trial processes and participant burden were acceptable, and participants highlighted physical and behavioural changes that they perceived to result from undertaking BRiMS. Engagement varied, influenced by a range of condition- and context-related factors. Suggestions to improve the utility and accessibility of BRiMS were highlighted.

CONCLUSIONS

The results suggest that the trial procedures are feasible and acceptable, and retention, programme engagement and outcome completion rates were sufficient to satisfy the a priori progression criteria. Challenges were experienced in some areas of data collection, such as completion of daily diaries.

FUTURE WORK

Further development of BRiMS is required to address logistical issues and enhance user-satisfaction and adherence. Following this, a definitive trial to assess the clinical effectiveness and cost-effectiveness of the BRiMS intervention is warranted.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN13587999.

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. 27. See the NIHR Journals Library website for further project information.

A group memory rehabilitation programme for people with traumatic brain injuries: the ReMemBrIn RCT

BACKGROUND

People with traumatic brain injuries (TBIs) commonly report memory impairments. These are persistent, debilitating and reduce quality of life, but patients do not routinely receive memory rehabilitation after discharge from hospital.

OBJECTIVE

To assess the clinical effectiveness and cost-effectiveness of a group memory rehabilitation programme for people with TBI.

DESIGN

Multicentre, pragmatic, cluster randomised controlled trial. Qualitative and health economic evaluations were also undertaken.

SETTING

Community settings in nine sites in England.

PARTICIPANTS

Participants were aged 18-69 years, had undergone a TBI > 3 months prior to recruitment, reported memory problems, were able to travel to a site to attend group sessions, could communicate in English and gave informed consent.

RANDOMISATION AND BLINDING

Clusters of four to six participants were randomised to the memory rehabilitation arm or the usual-care arm on a 1 : 1 ratio. Randomisation was based on a computer-generated pseudo-random code using random permuted blocks of randomly varying size, stratified by study site. Participants and therapists were aware of the treatment allocation whereas outcome assessors were blinded.

INTERVENTIONS

In the memory rehabilitation arm 10 weekly sessions of a manualised memory rehabilitation programme were provided in addition to usual care. Participants were taught restitution strategies to retrain impaired memory functions and compensation strategies to enable them to cope with memory problems. The usual-care arm received usual care only.

MAIN OUTCOME MEASURES

Outcomes were assessed at 6 and 12 months after randomisation. Primary outcome: patient-completed Everyday Memory Questionnaire - patient version (EMQ-p) at 6 months' follow-up. Secondary outcomes: Rivermead Behavioural Memory Test - third edition (RBMT-3), General Health Questionnaire 30-item version, European Brain Injury Questionnaire, Everyday Memory Questionnaire - relative version and individual goal attainment. Costs (based on a UK NHS and Personal Social Services perspective) were collected using a service use questionnaire, with the EuroQol-5 Dimensions, five-level version, used to derive quality-adjusted life-years (QALYs). A Markov model was developed to explore cost-effectiveness at 5 and 10 years, with a 3.5% discount applied.

RESULTS

We randomised 328 participants (memory rehabilitation, n = 171; usual care, n = 157), with 129 in the memory rehabilitation arm and 122 in the usual-care arm included in the primary analysis. We found no clinically important difference on the EMQ-p between the two arms at 6 months' follow-up (adjusted difference in mean scores -2.1, 95% confidence interval -6.7 to 2.5; p = 0.37). For secondary outcomes, differences favouring the memory rehabilitation arm were observed at 6 months' follow-up for the RBMT-3 and goal attainment, but remained only for goal attainment at 12 months' follow-up. There were no differences between arms in mood or quality of life. The qualitative results suggested positive experiences of participating in the trial and of attending the groups. Participants reported that memory rehabilitation was not routinely accessible in usual care. The primary health economics outcome at 12 months found memory rehabilitation to be £26.89 cheaper than usual care but less effective, with an incremental QALY loss of 0.007. Differences in costs and effects were not statistically significant and non-parametric bootstrapping demonstrated considerable uncertainty in these findings. No safety concerns were raised and no deaths were reported.

LIMITATIONS

As a pragmatic trial, we had broad inclusion criteria and, therefore, there was considerable heterogeneity within the sample. The study was not powered to perform further subgroup analyses. Participants and therapists could not be blinded to treatment allocation.

CONCLUSIONS

The group memory rehabilitation delivered in this trial is very unlikely to lead to clinical benefits or to be a cost-effective treatment for people with TBI in the community. Future studies should examine the selection of participants who may benefit most from memory rehabilitation.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN65792154.

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. 16. See the NIHR Journals Library website for further project information.

Incorporating pragmatic features into power analysis for cluster randomized trials with a count outcome

Cluster randomized designs are frequently employed in pragmatic clinical trials which test interventions in the full spectrum of everyday clinical settings in order to maximize applicability and generalizability. In this study, we propose to directly incorporate pragmatic features into power analysis for cluster randomized trials with count outcomes. The pragmatic features considered include arbitrary randomization ratio, overdispersion, random variability in cluster size, and unequal lengths of follow-up over which the count outcome is measured. The proposed method is developed based on generalized estimating equation (GEE) and it is advantageous in that the sample size formula retains a closed form, facilitating its implementation in pragmatic trials. We theoretically explore the impact of various pragmatic features on sample size requirements. An efficient Jackknife algorithm is presented to address the problem of underestimated variance by the GEE sandwich estimator when the number of clusters is small. We assess the performance of the proposed sample size method through extensive simulation and an application example to a real clinical trial is presented.

Study protocol: Using peer support to aid in prevention and treatment in prediabetes (UPSTART)

BACKGROUND

There is an urgent need to develop and evaluate effective and scalable interventions to prevent or delay the onset of type 2 diabetes mellitus (T2DM).

METHODS

In this randomized controlled pragmatic trial, 296 adults with prediabetes will be randomized to either a peer support arm or enhanced usual care. Participants in the peer support arm meet face-to-face initially with a trained peer coach who also is a patient at the same health center to receive information on locally available wellness and diabetes prevention programs, discuss behavioral goals related to diabetes prevention, and develop an action plan for the next week to meet their goals. Over six months, peer coaches call their assigned participants weekly to provide support for weekly action steps. In the final 6 months, coaches call participants at least once monthly. Participants in the enhanced usual care arm receive information on local resources and periodic updates on available diabetes prevention programs and resources. Changes in A1c, weight, waist circumference and other patient-centered outcomes and mediators and moderators of intervention effects will be assessed.

RESULTS

At least 296 participants and approximately 75 peer supporters will be enrolled.

DISCUSSION

Despite evidence that healthy lifestyle interventions can improve health behaviors and reduce risk for T2DM, engagement in recommended behavior change is low. This is especially true among racial and ethnic minority and low-income adults. Regular outreach and ongoing support from a peer coach may help participants to initiate and sustain healthy behavior changes to reduce their risk of diabetes.

TRIAL REGISTRATION

The ClinicalTrials.gov registration number is NCT03689530.

Protocol for a partially nested randomised controlled trial to evaluate the effectiveness of the scleroderma patient-centered intervention network COVID-19 home-isolation activities together (SPIN-CHAT) program to reduce anxiety among at-risk scleroderma patients

OBJECTIVE

Contagious disease outbreaks and related restrictions can lead to negative psychological outcomes, particularly in vulnerable populations at risk due to pre-existing medical conditions. No randomised controlled trials (RCTs) have tested interventions to reduce mental health consequences of contagious disease outbreaks. The primary objective of the Scleroderma Patient-centered Intervention Network COVID-19 Home-isolation Activities Together (SPIN-CHAT) Trial is to evaluate the effect of a videoconference-based program on symptoms of anxiety. Secondary objectives include evaluating effects on symptoms of depression, stress, loneliness, boredom, physical activity, and social interaction.

METHODS

The SPIN-CHAT Trial is a pragmatic RCT that will be conducted using the SPIN-COVID-19 Cohort, a sub-cohort of the SPIN Cohort. Eligible participants will be SPIN-COVID-19 Cohort participants without a positive COVID-19 test, with at least mild anxiety (PROMIS Anxiety 4a v1.0 T-score ≥ 55), not working from home, and not receiving current counselling or psychotherapy. We will randomly assign 162 participants to intervention groups of 7 to 10 participants each or waitlist control. We will use a partially nested RCT design to reflect dependence between individuals in training groups but not in the waitlist control. The SPIN-CHAT Program includes activity engagement, education on strategies to support mental health, and mutual participant support. Intervention participants will receive the 4-week (3 sessions per week) SPIN-CHAT Program via videoconference. The primary outcome is PROMIS Anxiety 4a score immediately post-intervention.

ETHICS AND DISSEMINATION

The SPIN-CHAT Trial will test whether a brief videoconference-based intervention will improve mental health outcomes among at-risk individuals during contagious disease outbreak.

A tutorial on sample size calculation for multiple-period cluster randomized parallel, cross-over and stepped-wedge trials using the Shiny CRT Calculator

It has long been recognized that sample size calculations for cluster randomized trials require consideration of the correlation between multiple observations within the same cluster. When measurements are taken at anything other than a single point in time, these correlations depend not only on the cluster but also on the time separation between measurements and additionally, on whether different participants (cross-sectional designs) or the same participants (cohort designs) are repeatedly measured. This is particularly relevant in trials with multiple periods of measurement, such as the cluster cross-over and stepped-wedge designs, but also to some degree in parallel designs. Several papers describing sample size methodology for these designs have been published, but this methodology might not be accessible to all researchers. In this article we provide a tutorial on sample size calculation for cluster randomized designs with particular emphasis on designs with multiple periods of measurement and provide a web-based tool, the Shiny CRT Calculator, to allow researchers to easily conduct these sample size calculations. We consider both cross-sectional and cohort designs and allow for a variety of assumed within-cluster correlation structures. We consider cluster heterogeneity in treatment effects (for designs where treatment is crossed with cluster), as well as individually randomized group-treatment trials with differential clustering between arms, for example designs where clustering arises from interventions being delivered in groups. The calculator will compute power or precision, as a function of cluster size or number of clusters, for a wide variety of designs and correlation structures. We illustrate the methodology and the flexibility of the Shiny CRT Calculator using a range of examples.

Managing clustering effects and learning effects in the design and analysis of multicentre randomised trials: a survey to establish current practice

Background

Patient outcomes can depend on the treating centre, or health professional, delivering the intervention. A health professional’s skill in delivery improves with experience, meaning that outcomes may be associated with learning. Considering differences in intervention delivery at trial design will ensure that any appropriate adjustments can be made during analysis. This work aimed to establish practice for the allowance of clustering and learning effects in the design and analysis of randomised multicentre trials.

Methods

A survey that drew upon quotes from existing guidelines, references to relevant publications and example trial scenarios was delivered. Registered UK Clinical Research Collaboration Registered Clinical Trials Units were invited to participate.

Results

Forty-four Units participated (N = 50). Clustering was managed through design by stratification, more commonly by centre than by treatment provider. Managing learning by design through defining a minimum expertise level for treatment provider was common (89%). One-third reported experience in expertise-based designs. The majority of Units had adjusted for clustering during analysis, although approaches varied. Analysis of learning was rarely performed for the main analysis (n = 1), although it was explored by other means. The insight behind the approaches used within and reasons for, or against, alternative approaches were provided.

Conclusions

Widespread awareness of challenges in designing and analysing multicentre trials is identified. Approaches used, and opinions on these, vary both across and within Units, indicating that approaches are dependent on the type of trial. Agreeing principles to guide trial design and analysis across a range of realistic clinical scenarios should be considered.

Effectiveness of Group Problem Management Plus (Group-PM+) for adults affected by humanitarian crises in Nepal: study protocol for a cluster randomized controlled trial

BACKGROUND

Globally, the lack of availability of psychological services for people exposed to adversities has led to the development of a range of scalable psychological interventions with features that enable better scale-up. Problem Management Plus (PM+) is a brief intervention of five sessions that can be delivered by non-specialists. It is designed for people in communities in low- and middle-income countries (LMIC) affected by any kind of adversity. Two recent randomized controlled trials in Pakistan and Kenya demonstrated the effectiveness of individually delivered PM+. A group version of PM+ has been developed to make the intervention more scalable and acceptable. This paper describes the protocol for a cluster randomized controlled trial (c-RCT) on locally adapted Group PM+ in Nepal.

METHODS/DESIGN

This c-RCT will compare Group PM+ to enhanced usual care (EUC) in participants with high levels of psychological distress recruited from the community. The study is designed as a two-arm, single-blind c-RCT that will be conducted in a community-based setting in Morang, a flood affected district in Eastern Nepal. Randomization will occur at ward level, the smallest administrative level in Nepal, with 72 enrolled wards allocated to Group PM+ or to EUC (ratio 1:1). Group PM+ consists of five approximately 2.5-h sessions, in which participants are taught techniques to manage their stressors and problems, and is delivered by trained and supervised community psychosocial workers (CPSWs). EUC consists of a family meeting with (a) basic information on adversity and mental health, (b) benefits of getting support, (c) information on seeking services from local health facilities with mhGAP-trained staff. The primary outcome measure is levels of individual psychological distress at endline (equivalent to 20 ± 1 weeks after baseline), measured by the General Health Questionnaire (GHQ-12). Secondary outcome measures include levels of functioning, depressive symptoms, post-traumatic stress disorder symptoms, levels of social support, somatic symptoms, and ways of coping. We hypothesize that skills acquired will mediate any impact of the intervention.

DISCUSSION

This c-RCT will contribute to the growing evidence-base for transdiagnostic psychological interventions delivered by non-specialists for people in communities affected by adversity. If Group PM+ is proven effective, the intervention manual will be released for use, giving the opportunity for further adaptation and implementation of the intervention in diverse settings with communities that require better access to psychological interventions.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT03747055.

Changes in Firearm and Medication Storage Practices in Homes of Youths at Risk for Suicide: Results of the SAFETY Study, a Clustered, Emergency Department-Based, Multisite, Stepped-Wedge Trial

STUDY OBJECTIVE

We evaluate whether a counseling intervention implemented at the hospital level resulted in safer firearm and medication storage by caregivers of youths aged 10 to 17 years after their child's evaluation in the emergency department (ED) for a behavioral health concern.

METHODS

We used a stepped-wedge clustered design rolled out at 4 hospital sites to assess primary preregistered outcomes (self-reported storage changes caregivers made to household firearms and medications), assessed by survey 2 weeks after the ED visit. Three logistic models provided estimates of the intervention effect: an unadjusted model, a model with hospital-level fixed effects, and a model that further adjusts for time.

RESULTS

Of the 575 caregiver participants, 208 were firearm owners (123 in usual care, 85 in the intervention). Baseline (pre-ED visit) characteristics did not differ between usual care and intervention phases. During the 2-year study period, twice as many caregivers whose child visited the ED after (compared with before) a hospital adopted the intervention improved firearm storage and 3 times as many improved medication storage (odds ratio [OR]=2.1 [95% confidence interval {CI} 1.0 to ∞] and OR=3.0 [95% CI 2.2 to ∞], respectively). After adjusting for time, the intervention effect for medications persisted (OR=2.0 [95% CI 1.0 to ∞]); the effect on firearms did not (OR=0.7 [95% CI 0.1 to ∞]).

CONCLUSION

To our knowledge, this study is the first controlled trial to estimate the effectiveness of an intervention on firearm and medication storage in homes of youths at elevated risk of suicide. We found evidence that caregivers' medication storage improved after their child's ED visit, with evidence suggestive of improvement for firearm storage.

Optimal designs for group randomized trials and group administered treatments with outcomes at the subject and group level

With group randomized trials complete groups of subject are randomized to treatment conditions. Such grouping also occurs in individually randomized trials where treatment is administered in groups. Outcomes may be measured at the level of the subject, but also at the level of the group. The optimal design determines the number of groups and the number of subjects per group in the intervention and control conditions. It is found by taking a budgetary constraint into account, where costs are associated with implementing the intervention and control, and with taking measurements on subject and groups. The optimal design is found such that the effect of treatment is estimated with highest efficiency, and the total costs do not exceed the budget that is available. The design that is optimal for the outcome at the subject level is not necessarily optimal for the outcome at the group level. Multiple-objective optimal designs consider both outcomes simultaneously. Their aim is to find a design that has high efficiencies for both outcome measures. An Internet application for finding the multiple-objective optimal design is demonstrated on the basis of an example from smoking prevention in primary education, and another example on consultation time in primary care.

Statistical power in partially nested designs probing multilevel mediation

Objective: Analysis of the intermediate behaviors and mechanisms through which innovative therapies come to shape outcomes is a critical objective in many areas of psychotherapy research because it supports the iterative exploration, development and refinement of theories and therapies. Despite widespread interest in the intermediate behaviors and mechanisms that convey treatment effects, there is limited guidance on how to effectively and efficiently design studies to detect such mediated effects in the types of partially nested designs that commonly arise in psychotherapy research. In this study, we develop statistical power formulas to identify requisite sample sizes and guide the planning of studies probing mediation under two- and three-level partially nested designs. Method: We investigate multilevel mediation in partially nested structures and models for two- and three-level designs. Results: Well-powered studies probing mediation using partially nested designs will typically require moderate to large sample sizes or moderate to large effects. Discussion: We implement these formulas in the R package PowerUpR and a simple Shiny web application (https://poweruprshiny.shinyapps.io/PartiallyNestedMediationPower/) and demonstrate their use to plan studies using partially nested designs.

Clinical and cost effectiveness of a parent mediated intervention to reduce challenging behaviour in pre-schoolers with moderate to severe intellectual disability (EPICC-ID) study protocol: a multi-centre, parallel-group randomised controlled trial

BACKGROUND

Children with intellectual disabilities are likely to present with challenging behaviour. Parent mediated interventions have shown utility in influencing child behaviour, although there is a paucity of UK research into challenging behaviour interventions in this population. NICE guidelines favour Stepping Stones Triple P (SSTP) as a challenging behaviour intervention and this trial aims to evaluate its clinical and cost effectiveness in preschool children with moderate to severe intellectual disabilities.

METHODS

This trial launched in 2017 at four sites across England, with the aim of recruiting 258 participants (aged 30-59 months). The Intervention Group receive nine weeks of SSTP parenting therapy (six group sessions and three individualised face to face or telephone sessions) in addition to Treatment as Usual, whilst the Treatment as Usual only group receive other available services in each location. Both study groups undergo the study measurements at baseline and at four and twelve months. Outcome measures include parent reports and structured observations of behaviour. Service use and health related quality of life data will also be collected to carry out a cost effectiveness and utility evaluation.

DISCUSSION

Findings from this study will inform policy regarding interventions for challenging behaviour in young children with moderate to severe intellectual disabilities.

TRIAL REGISTRATION NUMBER

Clinicaltrials.gov, NCT03086876. Registered 22nd March 2017, https://clinicaltrials.gov/ct2/show/NCT03086876.

Challenges in the design, planning and implementation of trials evaluating group interventions

Background

Group interventions are interventions delivered to groups of people rather than to individuals and are used in healthcare for mental health recovery, behaviour change, peer support, self-management and/or health education. Evaluating group interventions in randomised controlled trials (RCTs) presents trialists with a set of practical problems, which are not present in RCTs of one-to-one interventions and which may not be immediately obvious.

Methods

Case-based approach summarising Sheffield trials unit’s experience in the design and implementation of five group interventions. We reviewed participant recruitment and attrition, facilitator training and attrition, attendance at the group sessions, group size and fidelity aspects across five RCTs.

Results

Median recruitment across the five trials was 3.2 (range 1.7–21.0) participants per site per month. Group intervention trials involve a delay in starting the intervention for some participants, until sufficient numbers are available to start a group. There was no evidence that the timing of consent, relative to randomisation, affected post-randomisation attrition which was a matter of concern for all trial teams. Group facilitator attrition was common in studies where facilitators were employed by the health system rather than the by the grant holder and led to the early closure of one trial; research sites responded by training ‘back-up’ and new facilitators. Trials specified that participants had to attend a median of 62.5% (range 16.7%–80%) of sessions, in order to receive a ‘therapeutic dose’; a median of 76.7% (range 42.9%–97.8%) received a therapeutic dose. Across the five trials, 75.3% of all sessions went ahead without the pre-specified ideal group size. A variety of methods were used to assess the fidelity of group interventions at a group and individual level across the five trials.

Conclusion

This is the first paper to provide an empirical basis for planning group intervention trials. Investigators should expect delays/difficulties in recruiting groups of the optimal size, plan for both facilitator and participant attrition, and consider how group attendance and group size affects treatment fidelity.

Trial registration

ISRCTN17993825 registered on 11/10/2016, ISRCTN28645428 registered on 11/04/2012, ISRCTN61215213 registered on 11/05/2011, ISRCTN67209155 registered on 22/03/2012, ISRCTN19447796 registered on 20/03/2014.

Group rumination-focused cognitive-behavioural therapy (CBT) v. group CBT for depression: phase II trial

BACKGROUND

Although cognitive-behavioural therapy (CBT) is an effective treatment for depression, less than half of patients achieve satisfactory symptom reduction during treatment. Targeting known psychopathological processes such as rumination may increase treatment efficacy. The aim of this study was to test whether adding group rumination-focused CBT (RFCBT) that explicitly targets rumination to routine medical management is superior to adding group CBT to routine medical management in treating major depression.

METHODS

A total of 131 outpatients with major depression were randomly allocated to 12 sessions group RFCBT v. group CBT, each in addition to routine medical management. The primary outcome was observer-rated symptoms of depression at the end of treatment measured on the Hamilton Rating Scale for Depression. Secondary outcomes were rumination at post-treatment and depressive symptoms at 6 months follow-up (Trial registered: NCT02278224).

RESULTS

RFCBT significantly improved observer-rated depressive symptoms (Cohen's d 0.38; 95% CI 0.03-0.73) relative to group CBT at post-treatment on the primary outcome. No post-treatment differences were found in rumination or in depressive symptoms at 6 months follow-up, although these secondary analyses may have been underpowered.

CONCLUSIONS

This is the first randomized controlled trial providing evidence of benefits of RFCBT in major depression compared with CBT. Group RFCBT may be a beneficial alternative to group CBT for major depression.

Cognitive behavioural therapy for the treatment of late life depression: study protocol of a multicentre, randomized, observer-blinded, controlled trial (CBTlate)

BACKGROUND

Late-life depression (LLD) is one of the most prevalent mental disorders in old age. It is associated with various adverse outcomes and frequent use of health care services thereby remaining a serious public health concern. Compared with depression in early adulthood, most treatment options of LLD are less effective. Psychotherapy may be particularly beneficial for LLD due to specific psychological conditions in old age and a low risk of side effects. Although cognitive behavioural therapy (CBT) is highly established and effective in depression in young and mid-life there is only a limited number of small studies on CBT in LLD. An LLD-specific CBT has not yet been compared to an active, but unspecific supportive psychological intervention in a multicentre trial.

METHODS

Here we present the design of the CBTlate trial, which is a multicentre, randomized, observer-blinded, active-controlled, parallel group trial. CBTlate aims at including 248 patients with LLD of both genders at 7 sites in Germany. The purpose of the study is to test the hypothesis that a 15-session individually-delivered CBT specific for LLD is of superior efficacy in reducing symptoms of depression in comparison with a supportive unspecific intervention (SUI) of the same quantity. The intervention includes 8 weeks of individual treatment sessions twice per week and a follow-up period of 6 months after randomization. The primary end point is the severity of depression at the end of treatment measured by the self-rated 30-item Geriatric Depression Scale (GDS). Secondary endpoints include depressive symptoms at week 5 and at follow-up (6 months after randomization). Additional secondary endpoints include the change of depressive symptoms assessed with a clinician-rating-scale and a patient reported outcome instrument for major depressive disorder, anxiety symptoms, sleep, cognition, quality of life, and overall health status from baseline to end-of treatment and to end of follow-up. Add-on protocols include MRI and the collection of blood samples.

DISCUSSION

This study is the first multicentre trial of a specific CBT intervention for LLD compared to an unspecific supportive psychological intervention administered in a specialist setting. It has important implications for developing and implementing efficient psychotherapeutic strategies for LLD and may be a significant step to broaden treatment options for people suffering from LLD.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT03735576, registered on 24 October 2018); DRKS (DRKS00013769, registered on 28 June 2018).

Essential Ingredients and Innovations in the Design and Analysis of Group-Randomized Trials

This article reviews the essential ingredients and innovations in the design and analysis of group-randomized trials. The methods literature for these trials has grown steadily since they were introduced to the biomedical research community in the late 1970s, and we summarize those developments. We review, in addition to the group-randomized trial, methods for two closely related designs, the individually randomized group treatment trial and the stepped-wedge group-randomized trial. After describing the essential ingredients for these designs, we review the most important developments in the evolution of their methods using a new bibliometric tool developed at the National Institutes of Health. We then discuss the questions to be considered when selecting from among these designs or selecting the traditional randomized controlled trial. We close with a review of current methods for the analysis of data from these designs, a case study to illustrate each design, and a brief summary.

Protocol for a partially nested randomized controlled trial to evaluate the effectiveness of the Scleroderma Patient-centered Intervention Network Support Group Leader EDucation (SPIN-SSLED) Program

BACKGROUND

Some people with rare diseases rely on peer-led support groups for disease-specific education and emotional and practical support. Systemic sclerosis (SSc), or scleroderma, is a rare autoimmune connective tissue disease. Many people with SSc cannot access support groups, and, when support groups exist, they may not be sustained due to challenges that could be addressed via leader training. The Scleroderma Patient-centered Intervention Network (SPIN), along with SSc patient organization partners, developed a training program for SSc patient support group leaders, the Scleroderma Support group Leader EDucation (SPIN-SSLED) Program. We recently completed a feasibility trial in which we successfully delivered the program to two groups of support group leaders who reported a high level of satisfaction with the program and its delivery. The primary objective of the full-scale SPIN-SSLED trial is to evaluate the effect of the program on support group leaders' self-efficacy for carrying out their leadership role. Secondary objectives include evaluating effects on leader burnout, leader satisfaction (participation efficacy), and emotional distress.

METHODS/DESIGN

The SPIN-SSLED trial is a pragmatic randomized controlled trial (RCT) in which 180 support group leaders will be randomly allocated to training groups of 6 participants each or to a waitlist control. We will use a partially nested RCT design to reflect dependence between individuals in training groups, but not in the waitlist control. Participants allocated to the training program will receive the 13-module SPIN-SSLED Program, delivered via webinar over the course of 3 months in weekly 60-90-min sessions. The primary outcome is leader self-efficacy, measured by the Scleroderma Support Group Leader Self-efficacy Scale post-intervention. Secondary outcomes are leader self-efficacy at 3 months post-intervention, and leader burnout, volunteer job satisfaction (participation efficacy), and emotional distress post-intervention and at 3 months post-intervention.

DISCUSSION

The SPIN-SSLED trial will test whether a training program for SSc patient support group leaders increases the self-efficacy of group leaders to carry out leadership tasks. The program has the potential to significantly improve the effectiveness and sustainability of existing SSc support groups, to increase the number of available support groups, and to be adapted for other chronic diseases.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT03965780. Registered on 29 May 2019.

Using n-Level Structural Equation Models for Causal Modeling in Fully Nested, Partially Nested, and Cross-Classified Randomized Controlled Trials

Complex data structures are ubiquitous in psychological research, especially in educational settings. In the context of randomized controlled trials, students are nested in classrooms but may be cross-classified by other units, such as small groups. Furthermore, in many cases only some students may be nested within a unit while other students may not. Such instances of partial nesting requires a more flexible framework for estimating treatment effects so that the model coefficients are correctly estimated. Although several recommendations have been offered to the field on handling partially nested data, few are comprehensive in their treatment of manifest and latent variables in the context of partial nesting, full nesting, and cross-classification. The present study introduces n-level structural equation modeling (SEM) as a flexible measurement and analytic framework for the estimation of treatment effects for complex data structures that frequently present in randomized controlled trials. In this tutorial, we explore how the notation of n-level SEM allows for parsimonious model specification whether data are observed or latent and in the presence of partial nested or cross-classified designs. By using the xxm package in R, the advantage of using n-level SEM framework is demonstrated through five examples for single outcome manifest variables, as in the traditional multilevel model, as well as latent applications as in multilevel SEM.

Don’t abandon RCTs in IVF. We don’t even understand them

The conclusion of the Human Fertilisation and Embryology Authority that ‘add-on’ therapies in IVF are not supported by high-quality evidence has prompted new questions regarding the role of the randomized controlled trial (RCT) in evaluating infertility treatments. Critics argue that trials are cumbersome tools that provide irrelevant answers. Instead, they argue that greater emphasis should be placed on large observational databases, which can be analysed using powerful algorithms to determine which treatments work and for whom. Although the validity of these arguments rests upon the sciences of statistics and epidemiology, the discussion to date has largely been conducted without reference to these fields. We aim to remedy this omission, by evaluating the arguments against RCTs in IVF from a primarily methodological perspective. We suggest that, while criticism of the status quo is warranted, a retreat from RCTs is more likely to make things worse for patients and clinicians.

Incisional negative pressure wound therapy for the prevention of surgical site infection after open lower limb revascularization - Rationale and design of a multi-center randomized controlled trial

Introduction

Lower limb revascularization with inguinal incisions is a common vascular surgical procedure. Due to risk of injury to lymphatic vessels and a diverse bacterial flora in the groin, surgical site infections (SSI) represent a common and sometimes life-threatening complication. While transverse incisions in endovascular aneurysm repair has a low SSI rate, vertical incisions in thrombendarterectomy (TEA) has a higher risk and bypass the highest risk. This randomized controlled trial (RCT) will investigate the protective role of negative pressure wound therapy (NPWT) on closed inguinal incisions in elective vascular surgery undergoing TEA and bypass procedures, respectively, to prevent SSI.

Methods

This RCT registered at ClinicalTrials.gov (Identifier: NCT01913132) compares the effects of a NPWT dressing (PICO™, Smith & Nephew, UK) to standard wound dressing on postoperative SSI. The multi-center study includes two distinct vascular procedures with different SSI risk profiles: TEA and lower limb bypass. Three hundred and fifty-eight groin incisions are anticipated to be included in the TEA group and 133 inguinal incisions in the bypass group. Bilateral inguinal incisions will be randomized to NPWT in one groin and control dressing in the contralateral groin, and this dependency was accounted for in sample size calculation and will be addressed in data analysis.

Discussion

This RCT attempts to evaluate the potential benefit of NPWT on closed inguinal incisions after two distinct vascular procedures at high risk of SSI. Outcome of this trial could have implications on postoperative wound care in both vascular and non-vascular surgical patients.

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.

Clinical and cost effectiveness of memory rehabilitation following traumatic brain injury: a pragmatic cluster randomized controlled trial

OBJECTIVE

To evaluate the clinical and cost effectiveness of a group-based memory rehabilitation programme for people with traumatic brain injury.

DESIGN

Multicentre, pragmatic, observer-blinded, randomized controlled trial in England.

SETTING

Community.

PARTICIPANTS

People with memory problems following traumatic brain injury, aged 18-69 years, able to travel to group sessions, communicate in English, and give consent.

INTERVENTIONS

A total of 10 weekly group sessions of manualized memory rehabilitation plus usual care (intervention) vs. usual care alone (control).

MAIN MEASURES

The primary outcome was the patient-reported Everyday Memory Questionnaire (EMQ-p) at six months post randomization. Secondary outcomes were assessed at 6 and 12 months post randomization.

RESULTS

We randomized 328 participants. There were no clinically important differences in the primary outcome between arms at six-month follow-up (mean EMQ-p score: 38.8 (SD 26.1) in intervention and 44.1 (SD 24.6) in control arms, adjusted difference in means: -2.1, 95% confidence interval (CI): -6.7 to 2.5, p = 0.37) or 12-month follow-up. Objectively assessed memory ability favoured the memory rehabilitation arm at the 6-month, but not at the 12-month outcome. There were no between-arm differences in mood, experience of brain injury, or relative/friend assessment of patient's everyday memory outcomes, but goal attainment scores favoured the memory rehabilitation arm at both outcome time points. Health economic analyses suggested that the intervention was unlikely to be cost effective. No safety concerns were raised.

CONCLUSION

This memory rehabilitation programme did not lead to reduced forgetting in daily life for a heterogeneous sample of people with traumatic brain injury. Further research will need to examine who benefits most from such interventions.

Embedding Self-Regulation Instruction Within Fractions Intervention for Third Graders With Mathematics Difficulties

The purpose of this study was to explore the efficacy of fractions intervention with and without an embedded self-regulation (SR) component for third-grade students at risk for mathematics disabilities. Fractions intervention focused on magnitude understanding and word problems. Embedded SR was designed to support a growth mindset (fostering belief that intellectual and academic abilities can be developed) along with SR processes in which students set goals, self-monitor, and use strategies to engage motivationally, metacognitively, and behaviorally through challenging tasks. Students (n = 69) were randomly assigned to business-as-usual control and the two versions of fractions intervention. Multilevel models, accounting for the nested structure of the data, identified a moderation effect on fraction word problems: For students receiving fractions intervention with embedded SR, response to intervention was robust across the continuum of students' pretest word problem skill; by contrast, without SR, response to fractions intervention depended on students' pretest word problem skill. On the remaining outcomes, results reflected stronger outcomes when fractions intervention embedded SR instruction without moderation.

Funders improved the management of learning and clustering effects through design and analysis of randomized trials involving surgery

OBJECTIVE

The objective of this study was to provide insight into current practice in planning for, and acknowledging, the presence of learning and clustering effects, by treating center and surgeon, when developing randomized surgical trials.

STUDY DESIGN AND SETTING

Complexities associated with delivering surgical interventions, such as clustering effects, by center or surgeon, and surgical learning should be considered at trial design. Main trial publications, within the wider literature, under-report these considerations. Funded applications, within a 4-year period, from a leading UK funding body were searched. Data were extracted on considerations for learning and clustering effects and the driver, funder, or applicant, behind these.

RESULTS

Fifty trials were eligible. Managing learning through establishing predefined center and surgeon credentials was common. One planned exploratory analysis of learning within center, and two within surgeon. Clustering, by site and surgeon, was often managed through stratifying randomization, with 81% and 60%, respectively, also planning to subsequently adjust analysis. One-third of responses to referees contained funder led changes accounting for learning and/or clustering.

CONCLUSION

This review indicates that researchers do consider impact of learning and clustering, by center and surgeon, during trial development. Furthermore, the funder is identified as a potential driver of considerations.

Improving cancer symptom awareness and help-seeking among adults living in socioeconomically deprived communities in the UK using a facilitated health check: A protocol for the Awareness and Beliefs About Cancer (ABACus) Randomised Control Trial

BACKGROUND

Cancer survival is lower in socioeconomically deprived communities, partly due to low awareness of symptoms, negative beliefs and delayed help-seeking. We developed an interactive health check questionnaire facilitated by trained lay advisors. It entails 29 questions about background, lifestyle and health with tailored behaviour change advice. Personalised results are printed using a traffic light (red/amber/green) system, highlighting areas where action should be taken. This is an individually randomised control trial to test effectiveness of the health check on symptom recognition.

METHODS

A total 246 participants aged 40+ years will be recruited from community and healthcare settings in socioeconomically deprived areas of Yorkshire and South Wales. Participants will be randomised to receive the health check or standard care (1:1 ratio). Outcome measures include: adapted Awareness and Beliefs about Cancer (primary outcome), brief State Trait Anxiety Inventory, intentions and motivation to adopt recommended health behaviours (early symptom presentation, cancer screening and lifestyle behaviours), adapted Client Service Receipt Inventory, brief medical history/screening and demographic questionnaire at: baseline; 2-weeks; and 6-months post-randomisation. A purposive sample of intervention sessions will be audio-recorded (n = 24) and half will additionally be observed (n = 12). Semi-structured interviews will take place at 2-weeks (n = 30) and 6-months (n = 15-20) post-randomisation. The primary analysis will compare cancer symptom recognition scores between arms at 2-weeks. Secondary analysis will assess cancer beliefs, barriers/time to presentation, screening and lifestyle behaviours, anxiety and costs. A process evaluation will assess intervention fidelity, dose and contamination. The London-Surrey NHS Research Ethics Committee (Ref: 17/LO/1507) approved this trial.

DISCUSSION

This is a trial of a theoretically underpinned complex intervention which has undergone phase 1 and 2 development work. The findings will evaluate evidence about the effect of the health check on symptom awareness. Although there are few exclusion criteria there are limitations regarding the population we are able to reach, who may have even higher risks of late diagnosis and poor cancer prognosis. However, the health check has the potential to improve cancer symptom awareness and encourage early help-seeking behaviour in deprived populations, thereby reducing inequalities in longer term cancer outcomes.

TRIAL REGISTRATION

Retrospectively registered with ISRCTN (Ref: ISRCTN16872545 ) on 12.01.2018.

Visit Planning Using a Waiting Room Health IT Tool: The Aligning Patients and Providers Randomized Controlled Trial

PURPOSE

Time during primary care visits is limited. We tested the hypothesis that a waiting room health information technology (IT) tool to help patients identify and voice their top visit priorities would lead to better visit interactions and improved quality of care.

METHODS

We designed a waiting room tool, the Visit Planner, to guide adult patients through the process of identifying their top priorities for their visit and effectively expressing these priorities to their clinician. We tested this tool in a cluster-randomized controlled trial with usual care as the control. Eligible patients had at least 1 clinical care gap (eg, overdue for cancer screening, suboptimal chronic disease risk factor control, or medication nonadherence).

RESULTS

The study (conducted March 31, 2016 through December 31, 2017) included 750 English- or Spanish-speaking patients. Compared with usual care patients, intervention patients more often reported "definitely" preparing questions for their doctor (59.5% vs 45.1%, P <.001) and "definitely" expressing their top concerns at the beginning of the visit (91.3% vs 83.3%, P = .005). Patients in both arms reported high levels of satisfaction with their care (86.8% vs 89.9%, P = .20). With 6 months of follow-up, prevalence of clinical care gaps was reduced by a similar amount in each study arm.

CONCLUSIONS

A simple waiting room-based tool significantly improved visit communication. Patients using the Visit Planner were more prepared and more likely to begin the visit by communicating their top priorities. These changes did not, however, lead to further reduction in aggregate clinical care gaps beyond the improvements seen in the usual care arm.

Statistical design and analysis in trials of proportionate interventions: a systematic review

BACKGROUND

In proportionate or adaptive interventions, the dose or intensity can be adjusted based on individual need at predefined decision stages during the delivery of the intervention. The development of such interventions may require an evaluation of the effectiveness of the individual stages in addition to the whole intervention. However, evaluating individual stages of an intervention has various challenges, particularly the statistical design and analysis. This review aimed to identify the use of trials of proportionate interventions and how they are being designed and analysed in current practice.

METHODS

We searched MEDLINE, Web of Science and PsycINFO for articles published between 2010 and 2015 inclusive. We considered trials of proportionate interventions in all fields of research. For each trial, its aims, design and analysis were extracted. The data synthesis was conducted using summary statistics and a narrative format.

RESULTS

Our review identified 44 proportionate intervention trials, comprising 28 trial results, 13 protocols and three secondary analyses. These were mostly described as stepped care (n=37) and mainly focussed on mental health research (n=30). The other studies were aimed at finding an optimal adaptive treatment strategy (n=7) in a variety of therapeutic areas. Further terminology used included adaptive intervention, staged intervention, sequentially multiple assignment trial or a two-phase design. The median number of decision stages in the interventions was two and only one study explicitly evaluated the effect of the individual stages.

CONCLUSIONS

Trials of proportionate staged interventions are being used predominantly within the mental health field. However, few studies consider the different stages of the interventions, either at the design or the analysis phase, and how they may interact with one another. There is a need for further guidance on the design, analyses and reporting across trials of proportionate interventions.

TRIAL REGISTRATION

Prospero, CRD42016033781. Registered on 2 February 2016.

Efficacy of individualized social competence training for children with oppositional defiant disorders/conduct disorders: a randomized controlled trial with an active control group

Patient-focused cognitive-behavioral therapy in children with aggressive behavior, which uses group-based social skills training, has resulted in significant reductions in behavioral problems, with effect sizes in the small-to-medium range. However, effects of individually delivered treatments and effects on aggressive behavior and comorbid conditions rated from different perspectives, child functional impairment, child quality of life, parent-child relationship, and parental psychopathology have rarely been assessed. In a randomized controlled trial, 91 boys aged 6-12 years with a diagnosis of oppositional defiant disorder/conduct disorder and peer-related aggression were randomized to receive individually delivered social competence training (Treatment Program for Children with Aggressive Behavior, THAV) or to an active control involving group play that included techniques to activate resources and the opportunity to train prosocial interactions in groups (PLAY). Outcome measures were rated by parents, teachers, or clinicians. Mostly moderate treatment effects for THAV compared to PLAY were found in parent ratings and/or clinician ratings on aggressive behavior, comorbid symptoms, psychosocial impairment, quality of life, parental stress, and negative expressed emotions. In teacher ratings, significant effects were found for ADHD symptoms and prosocial behavior only. THAV is a specifically effective intervention for boys aged 6-12 years with oppositional defiant disorder/conduct disorder and peer-related aggressive behavior as rated by parents and clinicians.

Visually Impaired OLder people’s Exercise programme for falls prevenTion (VIOLET): a feasibility study

Background

The visually impaired have a higher risk of falling and are likely to avoid activity.

Objectives

To adapt the existing Falls Management Exercise (FaME) programme, which is delivered in the community, for visually impaired older people (VIOP) and to investigate the feasibility of conducting a definitive randomised controlled trial of this adapted intervention.

Design

Phase I – consultation with stakeholders to adapt the existing programme. Two focus groups were conducted, each with 10 VIOP across the study sites. Phase II – two-centre randomised pilot trial and economic evaluation of the adapted programme for VIOP versus usual care. Phases III and IV – qualitative interviews with VIOP and Postural Stability Instructors regarding their views and experiences of the research process, undertaking the intervention and its acceptability.

Intervention

This was adapted from the group-based FaME programme. A 1-hour exercise programme ran weekly over 12 weeks at the study sites (Newcastle upon Tyne and Glasgow) and was delivered by third-sector organisations. Participants were advised to also exercise at home for 2 hours per week. Those randomised to the usual activities group received no intervention.

Outcome measures

These were completed at baseline, week 12 and week 24. The primary potential outcome measure used was the Short Form Falls Efficacy Scale – International. Secondary outcome assessment measures were activity avoidance, current activity, balance/falls risk, physical activity, loneliness, anxiety and depression, work and social adjustment, quality of life and economic costs. Participants’ compliance was assessed by reviewing attendance records and self-reported compliance with the home exercises. Instructors’ compliance with the course content (fidelity) was assessed by a researcher attending a sample of exercise sessions. Adverse events were collected in a weekly telephone call for all participants in both the intervention and control arm.

Findings

An adapted exercise programme was devised with stakeholders. In the pilot trial, 82 participants drawn from community-living VIOP were screened, 68 met the inclusion criteria and 64 were randomised, with 33 allocated to the intervention and 31 to the usual activities arm. A total of 94% of participants provided data at week 12 and 92% at week 24. Adherence to the study was high. The intervention was found to be both safe and acceptable to participants, with 76% attending nine or more classes. Median time for home exercise was 50 minutes per week. There was little or no evidence that fear of falling, exercise, attitudinal or quality-of-life outcomes differed between trial arms at follow-up. Thematic analysis of the interviews with VIOP participants identified facilitators of and barriers to exercise, including perceived relevance to health, well-being and lifestyle, social interaction, self-perception and practical assistance. Instructors identified issues regarding level of challenge and assistance from a second person.

Limitations

The small sample size and low falls risk of the study sample are study limitations.

Conclusion

Although adaptation, recruitment and delivery were successful, the findings (particularly from qualitative research with instructors and participants) indicated that VIOP with low to moderate falls risk could be integrated into mainstream programmes with some adaptations. A future definitive trial should consider graduated exercises appropriate to ability and falls risk within mainstream provision. Other outcome measures may additionally be considered.

Trial registration

Current Controlled Trials ISRCTN16949845.

Funding

This project was funded by the NIHR Public Health Research programme and will be published in full in Public Health Research; Vol. 7, No. 4. See the NIHR Journals Library website for further project information.

Sample size estimation and re-estimation of cluster randomized controlled trials for real-time feedback, debriefing, and retraining system of cardiopulmonary resuscitation for out-of-hospital cardiac arrests

Background

In cluster randomized controlled trials (RCTs) for emergency medical services (EMS) system, we encounter the situation that the actual cluster size and ratio of allocated patients between two groups eventually differ from those used for sample size estimation because of the nature of patient enrollment. In such trials, estimations of effect size of test intervention and intra-cluster correlation coefficient (ICC) used for sample size estimation are also difficult. To improve efficient management on clinical cluster RCTs, we need to understand the effect of such inconsistencies of the design parameters on the type I error rate and statistical power of testing.

Methods

We planned the trial which evaluated the 1-month favorable neurological survival of out-of-hospital cardiac arrest patients with or without real-time feedback, debriefing, and retraining system by EMS personnel. Under the conditions that we possibly encountered in this trial, we examined the effect of inconsistencies in the actual ICC, cluster size, and ratio of patient allocation with those expected for sample size estimation on the type I error rate and power, using simulation studies. We further investigated the contribution of incorporating sample size re-estimation, based on the results of interim analysis of the trial, on the power increase.

Results

This simulation study showed that the inconsistencies of cluster size and patient allocation ratio decreased the power by 5-10% in some cases. In addition, the power decreased by 3-4% when the actual ICC was larger than that expected for sample size estimation. Furthermore, the use of a generalized estimating equation method to evaluate the difference in the 1-month favorable neurological survival between two groups caused inflation of type I error rate. Finally, the increase in power by incorporating sample size re-estimation was limited.

Conclusions

We identified remarkable effects of sample size estimation and re-estimations in a cluster RCT for real-time feedback, debriefing, and retraining system of cardiopulmonary resuscitation for out-of-hospital cardiac arrests. The estimation of design parameters for sample size estimation is generally challenging in cluster RCTs for EMS system; therefore, it is important to conduct a trial simulation that assesses the statistical performances under sample sizes based on the various expected values of the design parameters before beginning the trial.

Using Moderator Analysis to Identify the First-Grade Children Who Benefit More and Less from a Reading Comprehension Program: A Step Toward Aptitude-by-Treatment Interaction

Because of the importance of teaching reading comprehension to struggling young readers and the infrequency with which it has been implemented and evaluated, we designed a comprehensive first-grade reading comprehension program. We conducted a component analysis of the program's decoding/fluency (DF) and reading comprehension (COMP) dimensions, creating DF and DF+COMP treatments to parse the value of COMP. Students (N = 125) were randomly assigned to the 2 active treatments and controls. Treatment children were tutored 3 times per week for 21 weeks in 45-min sessions. Children in DF and DF+COMP together performed more strongly than controls on word reading and comprehension. However, pretreatment word reading appeared to moderate these results such that children with weaker beginning word reading across the treatments outperformed similarly low-performing controls to a significantly greater extent than treatment children with stronger beginning word reading outperformed comparable controls. DF+COMP children did not perform better than DF children. Study limitations and implications for research and practice are discussed.

Appropriate statistical methods for analysing partially nested randomised controlled trials with continuous outcomes: a simulation study

Background

In individually randomised trials we might expect interventions delivered in groups or by care providers to result in clustering of outcomes for participants treated in the same group or by the same care provider. In partially nested randomised controlled trials (pnRCTs) this clustering only occurs in one trial arm, commonly the intervention arm. It is important to measure and account for between-cluster variability in trial design and analysis. We compare analysis approaches for pnRCTs with continuous outcomes, investigating the impact on statistical inference of cluster sizes, coding of the non-clustered arm, intracluster correlation coefficient (ICCs), and differential variance between intervention and control arm, and provide recommendations for analysis.

Methods

We performed a simulation study assessing the performance of six analysis approaches for a two-arm pnRCT with a continuous outcome. These include: linear regression model; fully clustered mixed-effects model with singleton clusters in control arm; fully clustered mixed-effects model with one large cluster in control arm; fully clustered mixed-effects model with pseudo clusters in control arm; partially nested homoscedastic mixed effects model, and partially nested heteroscedastic mixed effects model. We varied the cluster size, number of clusters, ICC, and individual variance between the two trial arms.

Results

All models provided unbiased intervention effect estimates. In the partially nested mixed-effects models, methods for classifying the non-clustered control arm had negligible impact. Failure to account for even small ICCs resulted in inflated Type I error rates and over-coverage of confidence intervals. Fully clustered mixed effects models provided poor control of the Type I error rates and biased ICC estimates. The heteroscedastic partially nested mixed-effects model maintained relatively good control of Type I error rates, unbiased ICC estimation, and did not noticeably reduce power even with homoscedastic individual variances across arms.

Conclusions

In general, we recommend the use of a heteroscedastic partially nested mixed-effects model, which models the clustering in only one arm, for continuous outcomes similar to those generated under the scenarios of our simulations study. However, with few clusters (3–6), small cluster sizes (5–10), and small ICC (≤0.05) this model underestimates Type I error rates and there is no optimal model.

Electronic supplementary material

The online version of this article (10.1186/s12874-018-0559-x) contains supplementary material, which is available to authorized users.

Reducing relapse and suicide in bipolar disorder: practical clinical approaches to identifying risk, reducing harm and engaging service users in planning and delivery of care – the PARADES (Psychoeducation, Anxiety, Relapse, Advance Directive Evaluation and Suicidality) programme

Background

Bipolar disorder (BD) costs £5.2B annually, largely as a result of incomplete recovery after inadequate treatment.

Objectives

A programme of linked studies to reduce relapse and suicide in BD.

Design

There were five workstreams (WSs): a pragmatic randomised controlled trial (RCT) of group psychoeducation (PEd) versus group peer support (PS) in the maintenance of BD (WS1); development and feasibility RCTs of integrated psychological therapy for anxiety in bipolar disorder (AIBD) and integrated for problematic alcohol use in BD (WS2 and WS3); survey and qualitative investigations of suicide and self-harm in BD (WS4); and survey and qualitative investigation of service users’ (SUs) and psychiatrists’ experience of the Mental Capacity Act 2005 (MCA), with reference to advance planning (WS5).

Setting

Participants were from England; recruitment into RCTs was limited to certain sites [East Midlands and North West (WS1); North West (WS2 and WS3)].

Participants

Aged ≥ 18 years. In WS1–3, participants had their diagnosis of BD confirmed by the Structural Clinical Interview for theDiagnostic and Statistical Manual of Mental Disorders.

Interventions

In WS1, group PEd/PS; in WS3 and WS4, individual psychological therapy for comorbid anxiety and alcohol use, respectively.

Main outcome measures

In WS1, time to relapse of bipolar episode; in WS2 and WS3, feasibility and acceptability of interventions; in WS4, prevalence and determinants of suicide and self-harm; and in WS5, professional training and support of advance planning in MCA, and SU awareness and implementation.

Results

Group PEd and PS could be routinely delivered in the NHS. The estimated median time to first bipolar relapse was 67.1 [95% confidence interval (CI) 37.3 to 90.9] weeks in PEd, compared with 48.0 (95% CI 30.6 to 65.9) weeks in PS. The adjusted hazard ratio was 0.83 (95% CI 0.62 to 1.11; likelihood ratio testp = 0.217). The interaction between the number of previous bipolar episodes (1–7 and 8–19, relative to 20+) and treatment arm was significant (χ2 = 6.80, degrees of freedom = 2;p = 0.034): PEd with one to seven episodes showed the greatest delay in time to episode. A primary economic analysis indicates that PEd is not cost-effective compared with PS. A sensitivity analysis suggests potential cost-effectiveness if decision-makers accept a cost of £37,500 per quality-adjusted life-year. AIBD and motivational interviewing (MI) cognitive–behavioural therapy (CBT) trials were feasible and acceptable in achieving recruitment and retention targets (AIBD:n = 72, 72% retention to follow-up; MI-CBT:n = 44, 75% retention) and in-depth qualitative interviews. There were no significant differences in clinical outcomes for either trial overall. The factors associated with risk of suicide and self-harm (longer duration of illness, large number of periods of inpatient care, and problems establishing diagnosis) could inform improved clinical care and specific interventions. Qualitative interviews suggested that suicide risk had been underestimated, that care needs to be more collaborative and that people need fast access to good-quality care. Despite SUs supporting advance planning and psychiatrists being trained in MCA, the use of MCA planning provisions was low, with confusion over informal and legally binding plans.

Limitations

Inferences for routine clinical practice from WS1 were limited by the absence of a ‘treatment as usual’ group.

Conclusion

The programme has contributed significantly to understanding how to improve outcomes in BD. Group PEd is being implemented in the NHS influenced by SU support.

Future work

Future work is needed to evaluate optimal approaches to psychological treatment of comorbidity in BD. In addition, work in improved risk detection in relation to suicide and self-harm in clinical services and improved training in MCA are indicated.

Trial registration

Current Controlled Trials ISRCTN62761948, ISRCTN84288072 and ISRCTN14774583.

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 inProgramme Grants for Applied Research; Vol. 6, No. 6. See the NIHR Journals Library website for further project information.

Multilevel factorial designs with experiment-induced clustering

Factorial experimental designs have many applications in the behavioral sciences. In the context of intervention development, factorial experiments play a critical role in building and optimizing high-quality, multicomponent behavioral interventions. One challenge in implementing factorial experiments in the behavioral sciences is that individuals are often clustered in social or administrative units and may be more similar to each other than to individuals in other clusters. This means that data are dependent within clusters. Power planning resources are available for factorial experiments in which the multilevel structure of the data is due to individuals' membership in groups that existed before experimentation. However, in many cases clusters are generated in the course of the study itself. Such experiment-induced clustering (EIC) requires different data analysis models and power planning resources from those available for multilevel experimental designs in which clusters exist prior to experimentation. Despite the common occurrence of both experimental designs with EIC and factorial designs, a bridge has yet to be built between EIC and factorial designs. Therefore, resources are limited or nonexistent for planning factorial experiments that involve EIC. This article seeks to bridge this gap by extending prior models for EIC, developed for single-factor experiments, to factorial experiments involving various types of EIC. We also offer power formulas to help investigators decide whether a particular experimental design involving EIC is feasible. We demonstrate that factorial experiments can be powerful and feasible even with EIC. We discuss design considerations and directions for future research. (PsycINFO Database Record

Optimal primary care management of clinical osteoarthritis and joint pain in older people: a mixed-methods programme of systematic reviews, observational and qualitative studies, and randomised controlled trials

Background

Osteoarthritis (OA) is the most common long-term condition managed in UK general practice. However, care is suboptimal despite evidence that primary care and community-based interventions can reduce OA pain and disability.

Objectives

The overall aim was to improve primary care management of OA and the health of patients with OA. Four parallel linked workstreams aimed to (1) develop a health economic decision model for estimating the potential for cost-effective delivery of primary care OA interventions to improve population health, (2) develop and evaluate new health-care models for delivery of core treatments and support for self-management among primary care consulters with OA, and to investigate prioritisation and implementation of OA care among the public, patients, doctors, health-care professionals and NHS trusts, (3) determine the effectiveness of strategies to optimise specific components of core OA treatment using the example of exercise and (4) investigate the effect of interventions to tackle barriers to core OA treatment, using the example of comorbid anxiety and depression in persons with OA.

Data sources

The North Staffordshire Osteoarthritis Project database, held by Keele University, was the source of data for secondary analyses in workstream 1.

Methods

Workstream 1 used meta-analysis and synthesis of published evidence about effectiveness of primary care treatments, combined with secondary analysis of existing longitudinal population-based cohort data, to identify predictors of poor long-term outcome (prognostic factors) and design a health economic decision model to estimate cost-effectiveness of different hypothetical strategies for implementing optimal primary care for patients with OA. Workstream 2 used mixed methods to (1) develop and test a ‘model OA consultation’ for primary care health-care professionals (qualitative interviews, consensus, training and evaluation) and (2) evaluate the combined effect of a computerised ‘pop-up’ guideline for general practitioners (GPs) in the consultation and implementing the model OA consultation on practice and patient outcomes (parallel group intervention study). Workstream 3 developed and investigated in a randomised controlled trial (RCT) how to optimise the effect of exercise in persons with knee OA by tailoring it to the individual and improving adherence. Workstream 4 developed and investigated in a cluster RCT the extent to which screening patients for comorbid anxiety and depression can improve OA outcomes. Public and patient involvement included proposal development, project steering and analysis. An OA forum involved public, patient, health professional, social care and researcher representatives to debate the results and formulate proposals for wider implementation and dissemination.

Results

This programme provides evidence (1) that economic modelling can be used in OA to extrapolate findings of cost-effectiveness beyond the short-term outcomes of clinical trials, (2) about ways of implementing support for self-management and models of optimal primary care informed by National Institute for Health and Care Excellence recommendations, including the beneficial effects of training in a model OA consultation on GP behaviour and of pop-up screens in GP consultations on the quality of prescribing, (3) against adding enhanced interventions to current effective physiotherapy-led exercise for knee OA and (4) against screening for anxiety and depression in patients with musculoskeletal pain as an addition to current best practice for OA.

Conclusions

Implementation of evidence-based care for patients with OA is feasible in general practice and has an immediate impact on improving the quality of care delivered to patients. However, improved levels of quality of care, changes to current best practice physiotherapy and successful introduction of psychological screening, as achieved by this programme, did not substantially reduce patients’ pain and disability. This poses important challenges for clinical practice and OA research.

Limitations

The key limitation in this work is the lack of improvement in patient-reported pain and disability despite clear evidence of enhanced delivery of evidence-based care.

Future work recommendations

(1) New thinking and research is needed into the achievable and desirable long-term goals of care for people with OA, (2) continuing investigation into the resources needed to properly implement clinical guidelines for management of OA as a long-term condition, such as regular monitoring to maintain exercise and physical activity and (3) new research to identify subgroups of patients with OA as a basis for stratified primary care including (i) those with good prognosis who can self-manage with minimal investigation or specialist treatment, (ii) those who will respond to, and benefit from, specific interventions in primary care, such as physiotherapy-led exercise, and (iii) develop research into effective identification and treatment of clinically important anxiety and depression in patients with OA and into the effects of pain management on psychological outcomes in patients with OA.

Trial registration

Current Controlled Trials ISRCTN06984617, ISRCTN93634563 and ISRCTN40721988.

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 inProgramme Grants for Applied Research Programme; Vol. 6, No. 4. See the NIHR Journals Library website for further project information.

Efficient design of cluster randomized trials with treatment-dependent costs and treatment-dependent unknown variances

Cluster randomized trials evaluate the effect of a treatment on persons nested within clusters, where treatment is randomly assigned to clusters. Current equations for the optimal sample size at the cluster and person level assume that the outcome variances and/or the study costs are known and homogeneous between treatment arms. This paper presents efficient yet robust designs for cluster randomized trials with treatment‐dependent costs and treatment‐dependent unknown variances, and compares these with 2 practical designs. First, the maximin design (MMD) is derived, which maximizes the minimum efficiency (minimizes the maximum sampling variance) of the treatment effect estimator over a range of treatment‐to‐control variance ratios. The MMD is then compared with the optimal design for homogeneous variances and costs (balanced design), and with that for homogeneous variances and treatment‐dependent costs (cost‐considered design). The results show that the balanced design is the MMD if the treatment‐to control cost ratio is the same at both design levels (cluster, person) and within the range for the treatment‐to‐control variance ratio. It still is highly efficient and better than the cost‐considered design if the cost ratio is within the range for the squared variance ratio. Outside that range, the cost‐considered design is better and highly efficient, but it is not the MMD. An example shows sample size calculation for the MMD, and the computer code (SPSS and R) is provided as supplementary material. The MMD is recommended for trial planning if the study costs are treatment‐dependent and homogeneity of variances cannot be assumed.

Cost-efficient designs for three-arm trials with treatment delivered by health professionals: Sample sizes for a combination of nested and crossed designs

Background This article studies the design of trials that compare three treatment conditions that are delivered by two types of health professionals. The one type of health professional delivers one treatment, and the other type delivers two treatments, hence, this design is a combination of a nested and crossed design. As each health professional treats multiple patients, the data have a nested structure. This nested structure has thus far been ignored in the design of such trials, which may result in an underestimate of the required sample size. In the design stage, the sample sizes should be determined such that a desired power is achieved for each of the three pairwise comparisons, while keeping costs or sample size at a minimum. Methods The statistical model that relates outcome to treatment condition and explicitly takes the nested data structure into account is presented. Mathematical expressions that relate sample size to power are derived for each of the three pairwise comparisons on the basis of this model. The cost-efficient design achieves sufficient power for each pairwise comparison at lowest costs. Alternatively, one may minimize the total number of patients. The sample sizes are found numerically and an Internet application is available for this purpose. The design is also compared to a nested design in which each health professional delivers just one treatment. Results Mathematical expressions show that this design is more efficient than the nested design. For each pairwise comparison, power increases with the number of health professionals and the number of patients per health professional. The methodology of finding a cost-efficient design is illustrated using a trial that compares treatments for social phobia. The optimal sample sizes reflect the costs for training and supervising psychologists and psychiatrists, and the patient-level costs in the three treatment conditions. Conclusion This article provides the methodology for designing trials that compare three treatment conditions while taking the nesting of patients within health professionals into account. As such, it helps to avoid underpowered trials. To use the methodology, a priori estimates of the total outcome variances and intraclass correlation coefficients must be obtained from experts' opinions or findings in the literature.

Modeling clustering and treatment effect heterogeneity in parallel and stepped-wedge cluster randomized trials

Cluster randomized trials are frequently used in health service evaluation. It is common practice to use an analysis model with a random effect to allow for clustering at the analysis stage. In designs where clusters are exposed to both control and treatment conditions, it may be of interest to examine treatment effect heterogeneity across clusters. In designs where clusters are not exposed to both control and treatment conditions, it can also be of interest to allow heterogeneity in the degree of clustering between arms. These two types of heterogeneity are related. It has been proposed in both parallel cluster trials, stepped-wedge, and other cross-over designs that this heterogeneity can be allowed for by incorporating additional random effect(s) into the model. Here, we show that the choice of model parameterization needs careful consideration as some parameterizations for additional heterogeneity induce unnecessary or implausible assumptions. We suggest more appropriate parameterizations, discuss their relative advantages, and demonstrate the implications of these model choices using a real example of a parallel cluster trial and a simulated stepped-wedge trial.

Treatment of maternal depression in urban slums of Karachi, Pakistan: A randomized controlled trial (RCT) of an integrated maternal psychological and early child development intervention

BACKGROUND

Maternal depression is a major public health problem. This may affect a mother's ability to provide adequate care for the child. The objective of this study was to evaluate the effectiveness of the Learning through Play Plus program (LTP Plus) - a parenting program integrated with Cognitive Behaviour Therapy (CBT).

METHODS

A total of 247 women with symptoms of depression in Karachi, Pakistan were assigned randomly to either LTP Plus or routine care (Clinical Trials Identifier: NCT00835016). Symptoms of maternal depression were measured using the Edinburgh Postnatal Depression Scale (EPDS) at 3 and 6 months after baseline.

RESULTS

At 3 months, there was a significant reduction in the EPDS scores in the intervention group compared to the routine group (adjusted mean difference [AMD] -3.65, 95% CI -6.14 to -1.15, p <0.004). This effect was sustained at 6 months (AMD -2.62, 95% CI -4.43 to -0.81, p<0.005). These women also reported less parental distress and disability. There was also a significant improvement in maternal knowledge about child development at 6 months.

CONCLUSION

There was a significant reduction in depression among women who received the group parenting program LTP Plus. This intervention has the potential to be scaled up and integrated with mother and child health programs.

Review of Recent Methodological Developments in Group-Randomized Trials: Part 2-Analysis

In 2004, Murray et al. reviewed methodological developments in the design and analysis of group-randomized trials (GRTs). We have updated that review with developments in analysis of the past 13 years, with a companion article to focus on developments in design. We discuss developments in the topics of the earlier review (e.g., methods for parallel-arm GRTs, individually randomized group-treatment trials, and missing data) and in new topics, including methods to account for multiple-level clustering and alternative estimation methods (e.g., augmented generalized estimating equations, targeted maximum likelihood, and quadratic inference functions). In addition, we describe developments in analysis of alternative group designs (including stepped-wedge GRTs, network-randomized trials, and pseudocluster randomized trials), which require clustering to be accounted for in their design and analysis.

Review of Recent Methodological Developments in Group-Randomized Trials: Part 1-Design

In 2004, Murray et al. reviewed methodological developments in the design and analysis of group-randomized trials (GRTs). We have highlighted the developments of the past 13 years in design with a companion article to focus on developments in analysis. As a pair, these articles update the 2004 review. We have discussed developments in the topics of the earlier review (e.g., clustering, matching, and individually randomized group-treatment trials) and in new topics, including constrained randomization and a range of randomized designs that are alternatives to the standard parallel-arm GRT. These include the stepped-wedge GRT, the pseudocluster randomized trial, and the network-randomized GRT, which, like the parallel-arm GRT, require clustering to be accounted for in both their design and analysis.

Study protocol: The Technology-Enhanced Coaching (TEC) program to improve diabetes outcomes - A randomized controlled trial

Background

Racial and ethnic minority adults with diabetes living in under-resourced communities face multiple barriers to sustaining self-management behaviors necessary to improve diabetes outcomes. Peer support and decision support tools each have been associated with improved diabetes outcomes.

Methods

290 primarily African American adults with poor glycemic control were recruited from the Detroit Veteran's Administration Hospital and randomized to Technology-Enhanced Coaching (TEC) or Peer Coaching alone. Participants in both arms were assigned a peer coach trained in autonomy-supportive approaches. Coaches are diabetes patients with prior poor glycemic control who now have good control. Participants met face-to-face initially with their coach to review diabetes education materials and develop an action plan. Educational materials in the TEC arm are delivered via a web-based, educational tool tailored with each participant's personalized health data (iDecide). Over six months, coaches call their assigned participants once a week to provide support for weekly action steps. Data are also collected on an Observational Control group with no contact with study staff. Changes in A1c, blood pressure, other patient-centered outcomes and mediators and moderators of intervention effects will be assessed.

Results

290 participants were enrolled.

Discussion

Tailored e-Health tools with educational content may enhance the effectiveness of peer coaching programs to better prepare patients to set self-management goals, identify action plans, and discuss treatment options with their health care providers. The study will provide insights for scalable self-management support programs for diabetes and chronic illnesses that require high levels of sustained patient self-management.

Multilevel Interventions Targeting Obesity: Research Recommendations for Vulnerable Populations

INTRODUCTION

The origins of obesity are complex and multifaceted. To be successful, an intervention aiming to prevent or treat obesity may need to address multiple layers of biological, social, and environmental influences.

METHODS

NIH recognizes the importance of identifying effective strategies to combat obesity, particularly in high-risk and disadvantaged populations with heightened susceptibility to obesity and subsequent metabolic sequelae. To move this work forward, the National Heart, Lung, and Blood Institute, in collaboration with the NIH Office of Behavioral and Social Science Research and NIH Office of Disease Prevention convened a working group to inform research on multilevel obesity interventions in vulnerable populations. The working group reviewed relevant aspects of intervention planning, recruitment, retention, implementation, evaluation, and analysis, and then made recommendations.

RESULTS

Recruitment and retention techniques used in multilevel research must be culturally appropriate and suited to both individuals and organizations. Adequate time and resources for preliminary work are essential. Collaborative projects can benefit from complementary areas of expertise and shared investigations rigorously pretesting specific aspects of approaches. Study designs need to accommodate the social and environmental levels under study, and include appropriate attention given to statistical power. Projects should monitor implementation in the multiple venues and include a priori estimation of the magnitude of change expected within and across levels.

CONCLUSIONS

The complexity and challenges of delivering interventions at several levels of the social-ecologic model require careful planning and implementation, but hold promise for successful reduction of obesity in vulnerable populations.

A brief intervention for weight control based on habit-formation theory delivered through primary care: results from a randomised controlled trial

BACKGROUND

Primary care is the 'first port of call' for weight control advice, creating a need for simple, effective interventions that can be delivered without specialist skills. Ten Top Tips (10TT) is a leaflet based on habit-formation theory that could fill this gap. The aim of the current study was to test the hypothesis that 10TT can achieve significantly greater weight loss over 3 months than 'usual care'.

METHODS

A two-arm, individually randomised, controlled trial in primary care. Adults with obesity were identified from 14 primary care providers across England. Patients were randomised to either 10TT or 'usual care' and followed up at 3, 6, 12, 18 and 24 months. The primary outcome was weight loss at 3 months, assessed by a health professional blinded to group allocation. Difference between arms was assessed using a mixed-effect linear model taking into account the health professionals delivering 10TT, and adjusted for baseline weight. Secondary outcomes included body mass index, waist circumference, the number achieving a 5% weight reduction, clinical markers for potential comorbidities, weight loss over 24 months and basic costs.

RESULTS

Five-hundred and thirty-seven participants were randomised to 10TT (n=267) or to 'usual care' (n=270). Data were available for 389 (72%) participants at 3 months and for 312 (58%) at 24 months. Participants receiving 10TT lost significantly more weight over 3 months than those receiving usual care (mean difference =-0.87kg; 95% confidence interval: -1.47 to -0.27; P=0.004). At 24 months, the 10TT group had maintained their weight loss, but the 'usual care' group had lost a similar amount. The basic cost of 10TT was low, that is, around £23 ($32) per participant.

CONCLUSIONS

The 10TT leaflet delivered through primary care is effective in the short-term and a low-cost option over the longer term. It is the first habit-based intervention to be used in a health service setting and offers a low-intensity alternative to 'usual care'.