Adherence to key recommendations for design and analysis of stepped-wedge cluster randomized trials: A review of trials published 2016-2022.

BACKGROUND/AIMS: The stepped-wedge cluster randomized trial (SW-CRT), in which clusters are randomized to a time at which they will transition to the intervention condition - rather than a trial arm - is a relatively new design. SW-CRTs have additional design and analytical considerations compared to conventional parallel arm trials. To inform future methodological development, including guidance for trialists and the selection of parameters for statistical simulation studies, we conducted a review of recently published SW-CRTs. Specific objectives were to describe (1) the types of designs used in practice, (2) adherence to key requirements for statistical analysis, and (3) practices around covariate adjustment. We also examined changes in adherence over time and by journal impact factor. METHODS: We used electronic searches to identify primary reports of SW-CRTs published 2016-2022. Two reviewers extracted information from each trial report and its protocol, if available, and resolved disagreements through discussion. RESULTS: We identified 160 eligible trials, randomizing a median (Q1-Q3) of 11 (8-18) clusters to 5 (4-7) sequences. The majority (122, 76%) were cross-sectional (almost all with continuous recruitment), 23 (14%) were closed cohorts and 15 (9%) open cohorts. Many trials had complex design features such as multiple or multivariate primary outcomes (50, 31%) or time-dependent repeated measures (27, 22%). The most common type of primary outcome was binary (51%); continuous outcomes were less common (26%). The most frequently used method of analysis was a generalized linear mixed model (112, 70%); generalized estimating equations were used less frequently (12, 8%). Among 142 trials with fewer than 40 clusters, only 9 (6%) reported using methods appropriate for a small number of clusters. Statistical analyses clearly adjusted for time effects in 119 (74%), for within-cluster correlations in 132 (83%), and for distinct between-period correlations in 13 (8%). Covariates were included in the primary analysis of the primary outcome in 82 (51%) and were most often individual-level covariates; however, clear and complete pre-specification of covariates was uncommon. Adherence to some key methodological requirements (adjusting for time effects, accounting for within-period correlation) was higher among trials published in higher versus lower impact factor journals. Substantial improvements over time were not observed although a slight improvement was observed in the proportion accounting for a distinct between-period correlation. CONCLUSIONS: Future methods development should prioritize methods for SW-CRTs with binary or time-to-event outcomes, small numbers of clusters, continuous recruitment designs, multivariate outcomes, or time-dependent repeated measures. Trialists, journal editors, and peer reviewers should be aware that SW-CRTs have additional methodological requirements over parallel arm designs including the need to account for period effects as well as complex intracluster correlations.

Prevalence of patient partner authorship and acknowledgment in child health research publications: an umbrella review.

OBJECTIVES: Children and families are increasingly involved as equal partners in child health research, however, considerations around authorship have received little attention and there is limited guidance on the topic. Our objective was to determine the frequency and nature of patient partner authorship and/or acknowledgment among articles focused on patient engagement in child health research. STUDY DESIGN AND SETTING: In this umbrella review, we searched MEDLINE, Embase, APA PsycINFO, Cochrane Database of Systematic Reviews, CINAHL, and Web of Science for systematic/scoping reviews on patient engagement in child health research. Individual articles included in eligible reviews comprised the sample of articles for analysis and were examined to identify patient partner authorship. Descriptive statistics were used to quantify patient partner authorship and/or acknowledgment and to summarize article characteristics. RESULTS: Twelve systematic/scoping reviews met eligibility criteria, from which 230 individual articles were examined. In 16/230 (7%) articles, there was at least one patient partner author, and in 6/230 (3%) articles, patient partners were included as group authors. Within article Acknowledgments sections, patient partners were acknowledged by name in 41/230 (18%) articles, and anonymously or as a group in 98/230 (43%) articles. Patient partner authorship and/or acknowledgment was more frequent among articles published more recently (after 2015) and among articles where patient engagement was explicitly reported in the article. CONCLUSION: Patient partners were more likely to be acknowledged than listed as an author on articles on patient engagement in child health research. Understanding patient partner preferences about authorship and acknowledgment, examination of the unique aspects of child and youth authorship and developing supports to empower patient partner authorship are needed.

Patient and public involvement in pragmatic trials: online survey of corresponding authors of published trials.

BACKGROUND: There are few data on patient and public involvement (PPI) in pragmatic trials. We aimed to describe the prevalence and nature of PPI within pragmatic trials, describe variation in prevalence of PPI by trial characteristics and compare prevalence of PPI reported by trial authors to that reported in trial publications. METHODS: We applied a search filter to identify pragmatic trials published from 2014 to 2019 in MEDLINE. We invited the corresponding authors of pragmatic trials to participate in an online survey about their specific trial. RESULTS: Of 3163 authors invited, 2585 invitations were delivered, 710 (27.5%) reported on 710 unique trials and completed the survey; 334 (47.0%) conducted PPI. Among those who conducted PPI, for many the aim was to increase the research relevance (86.3%) or quality (76.5%). Most PPI partners were engaged at protocol development stages (79.1%) and contributed to the co-design of interventions (70.9%) or recruitment or retention strategies (60.5%). Patient and public involvement was more common among trials involving children, trials conducted in the United Kingdom, cluster randomized trials, those explicitly labelled as "pragmatic" in the study manuscript, and more recent trials. Less than one-quarter of trials (22.8%) that reported PPI in the survey also reported PPI in the trial manuscript. INTERPRETATION: Nearly half of trialists in this survey reported conducting PPI and listed several benefits of doing so, but researchers who did not conduct PPI often cited a lack of requirement for it. Patient and public involvement appears to be significantly underreported in trial publications. Consistent and standardized reporting is needed to promote transparency about PPI methods, outcomes, challenges and benefits.

A scoping review described diversity in methods of randomization and reporting of baseline balance in stepped-wedge cluster randomized trials.

OBJECTIVES: In stepped-wedge cluster randomized trials (SW-CRTs), clusters are randomized not to treatment and control arms but to sequences dictating the times of crossing from control to intervention conditions. Randomization is an essential feature of this design but application of standard methods to promote and report on balance at baseline is not straightforward. We aimed to describe current methods of randomization and reporting of balance at baseline in SW-CRTs. STUDY DESIGN AND SETTING: We used electronic searches to identify primary reports of SW-CRTs published between 2016 and 2022. RESULTS: Across 160 identified trials, the median number of clusters randomized was 11 (Q1-Q3: 8-18). Sixty-three (39%) used restricted randomization-most often stratification based on a single cluster-level covariate; 12 (19%) of these adjusted for the covariate(s) in the primary analysis. Overall, 50 (31%) and 134 (84%) reported on balance at baseline on cluster- and individual-level characteristics, respectively. Balance on individual-level characteristics was most often reported by condition in cross-sectional designs and by sequence in cohort designs. Authors reported baseline imbalances in 72 (45%) trials. CONCLUSION: SW-CRTs often randomize a small number of clusters using unrestricted allocation. Investigators need guidance on appropriate methods of randomization and assessment and reporting of balance at baseline.

Health equity considerations in pragmatic trials in Alzheimer's and dementia disease: Results from a methodological review.

Introduction: To improve dementia care delivery for persons across all backgrounds, it is imperative that health equity is integrated into pragmatic trials. Methods: We reviewed 62 pragmatic trials of people with dementia published 2014 to 2019. We assessed health equity in the objectives; design, conduct, analysis; and reporting using PROGRESS-Plus which stands for Place of residence, Race/ethnicity, Occupation, Gender/sex, Religion, Education, Socioeconomic status, Social capital, and other factors such as age and disability. Results: Two (3.2%) trials incorporated equity considerations into their objectives; nine (14.5%) engaged with communities; 4 (6.5%) described steps to increase enrollment from equity-relevant groups. Almost all trials (59, 95.2%) assessed baseline balance for at least one PROGRESS-Plus characteristic, but only 10 (16.1%) presented subgroup analyses across such characteristics. Differential recruitment, attrition, implementation, adherence, and applicability across PROGRESS-Plus were seldom discussed. Discussion: Ongoing and future pragmatic trials should more rigorously integrate equity considerations in their design, conduct, and reporting. Highlights: Few pragmatic trials are explicitly designed to inform equity-relevant objectives.Few pragmatic trials take steps to increase enrollment from equity-relevant groups.Disaggregated results across equity-relevant groups are seldom reported.Adherence to existing tools (e.g., IMPACT Best Practices, CONSORT-Equity) is key.

Review of pragmatic trials found that multiple primary outcomes are common but so too are discrepancies between protocols and final reports.

OBJECTIVES: To describe prevalence of multiple primary outcomes, changes in primary outcomes and target sample sizes between protocols and final reports, and how issues of multiplicity are addressed in pragmatic trials. STUDY DESIGN AND SETTING: Individually randomized trials labeled as pragmatic, published 2014-2019 in MEDLINE and registered with ClinicalTrials.gov. RESULTS: We identified 262 final reports and located protocols for 159 (61%); primary outcomes were clearly reported in 145 (91%) protocols and 256 (98%) final reports. Thirty (19%) protocols and 38 (15%) final reports had multiple primary outcomes. Primary outcomes were present and identical in 128 (81%) matched protocol-final reports. Among 140 pairs with target sample sizes reported, 28 (20.0%) reduced their target sample size (mean 543 fewer participants per trial) and 16 (11.4%) increased it (mean 192 more participants per trial). Thirteen (29.5%) provided an explanation. Only 2 of 30 (7%) protocols and 4 of 38 (11%) final reports with co-primary outcomes explained how results would be interpreted in light of multiplicity; 21 of 30 (70%) protocols and 20 of 38 (53%) final reports accounted for co-primary outcomes in power calculations. CONCLUSION: Co-primary outcomes are common in pragmatic trials; improved transparency around design and analysis decisions involving co-primary outcomes is required.

Reporting of and explanations for under-recruitment and over-recruitment in pragmatic trials: a secondary analysis of a database of primary trial reports published from 2014 to 2019.

OBJECTIVES: To describe the extent to which pragmatic trials underachieved or overachieved their target sample sizes, examine explanations and identify characteristics associated with under-recruitment and over-recruitment. STUDY DESIGN AND SETTING: Secondary analysis of an existing database of primary trial reports published during 2014-2019, registered in ClinicalTrials.gov, self-labelled as pragmatic and with target and achieved sample sizes available. RESULTS: Of 372 eligible trials, the prevalence of under-recruitment (achieving <90% of target sample size) was 71 (19.1%) and of over-recruitment (>110% of target) was 87 (23.4%). Under-recruiting trials commonly acknowledged that they did not achieve their targets (51, 71.8%), with the majority providing an explanation, but only 11 (12.6%) over-recruiting trials acknowledged recruitment excess. The prevalence of under-recruitment in individually randomised versus cluster randomised trials was 41 (17.0%) and 30 (22.9%), respectively; prevalence of over-recruitment was 39 (16.2%) vs 48 (36.7%), respectively. Overall, 101 025 participants were recruited to trials that did not achieve at least 90% of their target sample size. When considering trials with over-recruitment, the total number of participants recruited in excess of the target was a median (Q1-Q3) 319 (75-1478) per trial for an overall total of 555 309 more participants than targeted. In multinomial logistic regression, cluster randomisation and lower journal impact factor were significantly associated with both under-recruitment and over-recruitment, while using exclusively routinely collected data and educational/behavioural interventions were significantly associated with over-recruitment; we were unable to detect significant associations with obtaining consent, publication year, country of recruitment or public engagement. CONCLUSIONS: A clear explanation for under-recruitment or over-recruitment in pragmatic trials should be provided to encourage transparency in research, and to inform recruitment to future trials with comparable designs. The issues and ethical implications of over-recruitment should be more widely recognised by trialists, particularly when designing cluster randomised trials.