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Aim: Open science, a set of principles and practices, aims to make scientific research more accessible and accountable, benefiting scientists and society. This study evaluated whether adopting open science practices (OSPs) correlates with higher citation rates and Altmetric scores., Methods: A random sample of randomised clinical trials (RCTs) on dental caries published between 2000 and 2022 was selected. A systematic PubMed search identified relevant RCTs, and data on OSPs - study registration, open methodology, open software, open scripts, open analysis plan, open data, open peer review, and open access (OA) - were manually collected by two independent assessors. The Robot Reviewer tool automatically evaluated the risk of bias (RoB). Outcomes included the total number of citations and the Altmetric Attention Score. Associations between OSPs, RoB, and other explanatory variables with the outcomes were assessed using binomial negative regression analysis, and expressed as Incidence Rate Ratio (IRR; α =0.05)., Results: In total, 323 papers were analysed. At least one OSP was adopted in 57.5 % (n = 186) of the articles, dropping to 39.6 % (n = 128) without OA. Papers with protocol registration (IRR: 1.45; 95 % CI: 1.15, 1.82) and OA publication (IRR: 1.24; 95 % CI: 1.01, 1.53) had higher citation rates. Conversely, papers in full OA journals had fewer citations (IRR: 0.67; 95 % CI: 0.52, 0.87). After adjusting for RoB, low-risk studies showed higher citation rates (IRR: 1.48; 95 % CI: 1.14, 1.91), while OA lost significance. For Altmetric scores, registered and OA manuscripts showed higher scores (IRR: 3.74; 95 % CI: 2.00, 7.01; IRR: 1.69; 95 % CI: 1.04, 2.75), with registration remaining significant after adjusting for RoB and impact factor (IRR: 3.71; 95 % CI: 1.97-6.99)., Conclusion: The adoption of OSPs demonstrated a partial correlation with citation rates and Altmetric scores in RCTs on dental caries; however, these effects are complex and seem more related to the journal's impact factor., Clinical Significance: The citations and the attention to clinical trials in dentistry, which could drive clinical decision-making and the elaboration of policies and recommendations, seem to be driven more by the journal's prestige than by the adoption of OSPs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Background: Cluster randomized trials (CRTs) are increasingly important for evaluating interventions embedded in health care systems. An essential parameter in sample size calculation to detect both overall and heterogeneous treatment effects for CRTs is the intra-cluster correlation coefficient (ICC) of both outcome and covariates of interest. However, obtaining advance estimates for the ICC can be challenging. When trial outcomes will be obtained from routinely collected data sources, there is an opportunity to obtain reliable ICC estimates in advance of the trial. Using USA national Medicare data, we estimated ICCs for a range of outcomes to inform the design of CRTs for people living with Alzheimer's and related dementias (ADRD)., Method: Data from 2018 Medicare Fee-for-Service beneficiaries, specifically, 1,898,812 individuals (≥ 65 years) with diagnosis of ADRD within 3436 hospital service areas (treated as clusters) and 306 hospital referral regions (treated as fixed strata), were used to calculate unadjusted and adjusted ICC estimates for three outcomes: death, any hospitalizations, and any emergency department (ED) visits and three covariates: age, race and sex. We present both overall and stratum-specific ICC estimates. We illustrate their use in sample size calculations for overall treatment effects as well as detecting treatment effect heterogeneity., Results: The unadjusted overall ICCs for death, hospitalizations, and ED visits were 0.001, 0.010, and 0.017 respectively. Stratum-specific ICCs varied widely across the 306 HRRs: median 0.001, 0.010 and 0.025 for death, hospitalizations, and ED visits respectively and 0.007, 0.001, and 0.080 for age, sex and race. An interactive R Shiny app is provided that allows users to retrieve estimates overlayed on a map of the USA., Conclusions: We presented both adjusted and unadjusted ICCs for outcomes as well as unadjusted ICCs for covariates of potential interest from population-level data in the USA and demonstrated how the estimates may be used in sample size calculations for CRTs in ADRD., (© 2024. The Author(s).)

Background: Dichotomisation of statistical significance, rather than interpretation of effect sizes supported by confidence intervals, is a long-standing problem., Methods: We distributed an online survey to clinical trial statisticians across the UK, Australia and Canada asking about their experiences, perspectives and practices with respect to interpretation of statistical findings from randomised trials. We report a descriptive analysis of the closed-ended questions and a thematic analysis of the open-ended questions., Results: We obtained 101 responses across a broad range of career stages (24% professors; 51% senior lecturers; 22% junior statisticians) and areas of work (28% early phase trials; 44% drug trials; 38% health service trials). The majority (93%) believed that statistical findings should be interpreted by considering (minimal) clinical importance of treatment effects, but many (61%) said quantifying clinically important effect sizes was difficult, and fewer (54%) followed this approach in practice. Thematic analysis identified several barriers to forming a consensus on the statistical interpretation of the study findings, including: the dynamics within teams, lack of knowledge or difficulties in communicating that knowledge, as well as external pressures. External pressures included the pressure to publish definitive findings and statistical review which can sometimes be unhelpful but can at times be a saving grace. However, the concept of the minimally important difference was identified as a particularly poorly defined, even nebulous, construct which lies at the heart of much disagreement and confusion in the field., Conclusion: The majority of participating statisticians believed that it is important to interpret statistical findings based on the clinically important effect size, but report this is difficult to operationalise. Reaching a consensus on the interpretation of a study is a social process involving disparate members of the research team along with editors and reviewers, as well as patients who likely have a role in the elicitation of minimally important differences., (© 2024. The Author(s).)

Purpose: Race-based correction is widely utilized in clinical practice, but may contribute to overestimation of lung function, underdiagnoses in minority groups, and exclusion of minority groups from research trials. The aim of this systematic review is to examine the usage of race-based correction in pulmonary function testing (PFT) within chronic obstructive lung disease (COPD) research and its impact on the exclusion of minority groups from research trials., Methods: We systematically searched Medline from 2010 to 2022 to identify randomized controlled trials (RCTs) that examine inhaler therapy for COPD. Article screening, critical appraisal, and data extraction were completed in duplicate by independent reviewers. Data regarding study design, inclusion criteria, demographics, and race-based correction were extracted and synthesized narratively., Results: Of the 774 screened articles, we included 21 RCTs in the review, which were multinational trials involving 70696 study participants. All studies had an inclusion criteria of an FEV 1 cutoff of 50% to 80%. Racial minorities remained underrepresented in the trials, with the proportion of black participants ranging from <1% to 4.7%. Four studies directly mentioned race-based correction, while the remainder of the studies did not provide any explicit details. After obtaining additional information by contacting authors and reviewing the citations, 15 were estimated to utilize race-based correction., Conclusion: Race-based correction may be frequently utilized in major COPD RCTs, but there remains inconsistent reporting regarding the usage of race-based correction. This may contribute to the exclusion of racialized populations from research trials as there remains significant underrepresentation of racialized populations from research., Competing Interests: The authors report no conflicts of interest in this work., (© 2024 Wang et al.)

Objective: Cluster randomised trials (CRTs) are used for evaluating health-related interventions in low-income and middle-income countries (LMICs) but raise complex ethical issues. To inform the development of future ethics guidance, we aim to characterise CRTs conducted exclusively in LMICs by examining the types of clusters, settings, author affiliations and primary clinical focus and to evaluate adherence to trial registration and ethics reporting requirements over time., Design: A systematic scoping review using the Preferred Reporting Items for Systematic Review and Meta-Analyses Extension for Scoping Reviews., Data Sources: We searched MEDLINE between 1 January 2017 and 17 August 2022., Eligibility Criteria for Selecting Studies: We included primary reports of CRTs evaluating health-related interventions, conducted exclusively in LMICs and published in English between 2017 and 2022., Data Extraction and Synthesis: Data were extracted by one reviewer; a second reviewer verified accuracy by extracting data from 10% of the reports. Results were summarised overall and categorised by country's economic level or publication year., Results: Among 800 identified CRTs, 400 (50.0%) randomised geographical areas and 373 (46.6%) were conducted in Africa. 30 (3.7%) had no authors with an LMIC affiliation, and 246 (30.8%) had neither first nor last author with an LMIC affiliation. The relative frequency of first or last authors holding an LMIC affiliation increases as a country's economic level increases. Most CRTs focused on reducing maternal and neonatal disorders (106, 13.3%). 670 (83.8%) CRTs reported trial registration, 786 (98.2%) reported research ethics committee review and 757 (94.6%) reported consent statements. Among the 757 CRTs, 46 (6.1%) reported a waiver or no consent and, among these, 10 (21.7%) did not provide a rationale. Gatekeepers were identified in 403 (50.4%) CRTs. No meaningful trends were observed in adherence to trial registration or ethics reporting requirements over time., Conclusion: Our findings suggest existing inequity in authorship practices. There is high adherence to trial registration and ethics reporting requirements, although greater attention to reporting a justification for using a waiver of consent is needed., Competing Interests: Competing interests: CW receives consulting income from Cardialen and Eli Lilly & Company. Other authors declare no competing interests., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Linear mixed models are commonly used in analyzing stepped-wedge cluster randomized trials. A key consideration for analyzing a stepped-wedge cluster randomized trial is accounting for the potentially complex correlation structure, which can be achieved by specifying random-effects. The simplest random effects structure is random intercept but more complex structures such as random cluster-by-period, discrete-time decay, and more recently, the random intervention structure, have been proposed. Specifying appropriate random effects in practice can be challenging: assuming more complex correlation structures may be reasonable but they are vulnerable to computational challenges. To circumvent these challenges, robust variance estimators may be applied to linear mixed models to provide consistent estimators of standard errors of fixed effect parameters in the presence of random-effects misspecification. However, there has been no empirical investigation of robust variance estimators for stepped-wedge cluster randomized trials. In this article, we review six robust variance estimators (both standard and small-sample bias-corrected robust variance estimators) that are available for linear mixed models in R, and then describe a comprehensive simulation study to examine the performance of these robust variance estimators for stepped-wedge cluster randomized trials with a continuous outcome under different data generators. For each data generator, we investigate whether the use of a robust variance estimator with either the random intercept model or the random cluster-by-period model is sufficient to provide valid statistical inference for fixed effect parameters, when these working models are subject to random-effect misspecification. Our results indicate that the random intercept and random cluster-by-period models with robust variance estimators performed adequately. The CR3 robust variance estimator (approximate jackknife) estimator, coupled with the number of clusters minus two degrees of freedom correction, consistently gave the best coverage results, but could be slightly conservative when the number of clusters was below 16. We summarize the implications of our results for the linear mixed model analysis of stepped-wedge cluster randomized trials and offer some practical recommendations on the choice of the analytic model., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background: There is no universally accepted definition for surgical prehabilitation. The objectives of this scoping review were to (1) identify how surgical prehabilitation is defined across randomised controlled trials and (2) propose a common definition., Methods: The final search was conducted in February 2023 using MEDLINE, Embase, PsycINFO, Web of Science, CINAHL, and Cochrane. We included randomised controlled trials (RCTs) of unimodal or multimodal prehabilitation interventions (nutrition, exercise, and psychological support) lasting at least 7 days in adults undergoing elective surgery. Qualitative data were analysed using summative content analysis., Results: We identified 76 prehabilitation trials of patients undergoing abdominal (n=26, 34%), orthopaedic (n=20, 26%), thoracic (n=14, 18%), cardiac (n=7, 9%), spinal (n=4, 5%), and other (n=5, 7%) surgeries. Surgical prehabilitation was explicitly defined in more than half of these RCTs (n=42, 55%). Our findings consolidated the following definition: 'Prehabilitation is a process from diagnosis to surgery, consisting of one or more preoperative interventions of exercise, nutrition, psychological strategies and respiratory training, that aims to enhance functional capacity and physiological reserve to allow patients to withstand surgical stressors, improve postoperative outcomes, and facilitate recovery.', Conclusions: A common definition is the first step towards standardisation, which is needed to guide future high-quality research and advance the field of prehabilitation. The proposed definition should be further evaluated by international stakeholders to ensure that it is comprehensive and globally accepted., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The temptation to use prospective observational studies (POS) instead of conducting difficult trials (RCTs) has always existed, but with the advent of powerful computers and large databases, it can become almost irresistible. We examine the potential consequences, were this to occur, by comparing two hypothetical studies of a new treatment: one RCT, and one POS. The POS inevitably submits more patients to inferior research methodology. In RCTs, patients are clearly informed of the research context, and 1:1 randomized allocation between experimental and validated treatment balances risks for each patient. In POS, for each patient, the risks of receiving inferior treatment are impossible to estimate. The research context and the uncertainty are down-played, and patients and clinicians are at risk of becoming passive research subjects in studies performed from an outsider's view, which potentially has extraneous objectives, and is conducted without their explicit, autonomous, and voluntary involvement and consent., (© The Author(s) 2024. Published by Oxford University Press, on behalf of the Journal of Medicine and Philosophy Inc. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Background: Heterogeneity of reported outcomes can impact the certainty of evidence for prehabilitation. The objective of this scoping review was to systematically map outcomes and assessment tools used in trials of surgical prehabilitation., Methods: MEDLINE, EMBASE, PsychInfo, Web of Science, CINAHL, and Cochrane were searched in February 2023. Randomised controlled trials of unimodal or multimodal prehabilitation interventions (nutrition, exercise, psychological support) lasting at least 7 days in adults undergoing elective surgery were included. Reported outcomes were classified according to the International Society for Pharmacoeconomics and Outcomes Research framework., Results: We included 76 trials, mostly focused on abdominal or orthopaedic surgeries. A total of 50 different outcomes were identified, measured using 184 outcome assessment tools. Observer-reported outcomes were collected in 86% of trials (n=65), with hospital length of stay being most common. Performance outcomes were reported in 80% of trials (n=61), most commonly as exercise capacity assessed by cardiopulmonary exercise testing. Clinician-reported outcomes were included in 78% (n=59) of trials and most frequently included postoperative complications with Clavien-Dindo classification. Patient-reported outcomes were reported in 76% (n=58) of trials, with health-related quality of life using the 36- or 12-Item Short Form Survey being most prevalent. Biomarker outcomes were reported in 16% of trials (n=12) most commonly using inflammatory markers assessed with C-reactive protein., Conclusions: There is substantial heterogeneity in the reporting of outcomes and assessment tools across surgical prehabilitation trials. Identification of meaningful outcomes, and agreement on appropriate assessment tools, could inform the development of a prehabilitation core outcomes set to harmonise outcome reporting and facilitate meta-analyses., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Objective: To evaluate the reporting of race/ethnicity data in randomized controlled trials (RCTs) of attention-deficit/hyperactivity disorder (ADHD) medications. Secondary objectives were to estimate temporal trends in the reporting, and to compare the pooled prevalence of racial/ethnic groups in RCTs conducted in the US to national estimates., Method: We drew on, adapted, and updated the search of a network meta-analysis by Cortese et al. (2018) up to March 2022. We calculated the percentage of RCTs reporting data on race/ethnicity of participants in the published article or in related unpublished material. Temporal trends were estimated with logistic regression. The pooled prevalence of each racial/ethnic group across US RCTs was calculated using random-effects model meta-analyses., Results: We retained 310 RCTs (including 44,447 participants), of which 231 were conducted in children/adolescents, 78 in adults, and 1 in both. Data on race/ethnicity were reported in 59.3% of the RCTs (75% of which were conducted in children/adolescents and 25% in adults) in the published article, and in unpublished material in an additional 8.7% of the RCTs. Reporting improved over time. In the US RCTs, Asian and White individuals were under- and overrepresented, respectively, compared to national estimates in the most recent time period considered., Conclusion: More than 30% of the RCTs of ADHD medications retained in this review did not include data on race/ethnicity in their published or unpublished reports, and more than 40% in their published articles, even though reporting improved over time. Results should inform investigators, authors, editors, regulators, and study participants in relation to efforts to tackle inequalities in ADHD research., Plain Language Summary: A systematic review of 310 randomized controlled trials for attention-deficit/hyperactivity disorder (ADHD) medications found that race/ethnicity were reported in only 30% of trials. Compared to national estimates, Asian individuals were underrepresented and non-Hispanic Whites individuals were overrepresented, drawing attention to the inequities in participation in ADHD research., Diversity & Inclusion Statement: One or more of the authors of this paper self-identifies as a member of one or more historically underrepresented racial and/or ethnic groups in science. We actively worked to promote sex and gender balance in our author group. While citing references scientifically relevant for this work, we also actively worked to promote sex and gender balance in our reference list. While citing references scientifically relevant for this work, we also actively worked to promote inclusion of historically underrepresented racial and/or ethnic groups in science in our reference list. The author list of this paper includes contributors from the location and/or community where the research was conducted who participated in the data collection, design, analysis, and/or interpretation of the work., Study Preregistration Information: Reporting and representation of race/ethnicity in double blind randomised controlled trials of medications for ADHD; https://osf.io/; hfgz8., (Copyright © 2024. Published by Elsevier Inc.)

Cluster-randomized trials (CRTs) often allocate intact clusters of participants to treatment or control conditions and are increasingly used to evaluate healthcare delivery interventions. While previous studies have developed sample size methods for testing confirmatory hypotheses of treatment effect heterogeneity in CRTs (i.e., targeting the difference between subgroup-specific treatment effects), sample size methods for testing the subgroup-specific treatment effects themselves have not received adequate attention-despite a rising interest in health equity considerations in CRTs. In this article, we develop formal methods for sample size and power analyses for testing subgroup-specific treatment effects in parallel-arm CRTs with a continuous outcome and a binary subgroup variable. We point out that the variances of the subgroup-specific treatment effect estimators and their covariance are given by weighted averages of the variance of the overall average treatment effect estimator and the variance of the heterogeneous treatment effect estimator. This analytical insight facilitates an explicit characterization of the requirements for both the omnibus test and the intersection-union test to achieve the desired level of power. Generalizations to allow for subgroup-specific variance structures are also discussed. We report on a simulation study to validate the proposed sample size methods and demonstrate that the empirical power corresponds well with the predicted power for both tests. The design and setting of the Umea Dementia and Exercise (UMDEX) CRT in older adults are used to illustrate our sample size methods., (© 2023. The Author(s).)

The cluster randomized crossover design has been proposed to improve efficiency over the traditional parallel-arm cluster randomized design. While statistical methods have been developed for designing cluster randomized crossover trials, they have exclusively focused on testing the overall average treatment effect, with little attention to differential treatment effects across subpopulations. Recently, interest has grown in understanding whether treatment effects may vary across pre-specified patient subpopulations, such as those defined by demographic or clinical characteristics. In this article, we consider the two-treatment two-period cluster randomized crossover design under either a cross-sectional or closed-cohort sampling scheme, where it is of interest to detect the heterogeneity of treatment effect via an interaction test. Assuming a patterned correlation structure for both the covariate and the outcome, we derive new sample size formulas for testing the heterogeneity of treatment effect with continuous outcomes based on linear mixed models. Our formulas also address unequal cluster sizes and therefore allow us to analytically assess the impact of unequal cluster sizes on the power of the interaction test in cluster randomized crossover designs. We conduct simulations to confirm the accuracy of the proposed methods, and illustrate their application in two real cluster randomized crossover trials., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background: An estimated one-quarter to one-half of people diagnosed with haematological malignancies experience anaemia. There are different strategies for red blood cell (RBC) transfusions to treat anaemia. A restrictive transfusion strategy permits a lower haemoglobin (Hb) level whereas a liberal transfusion strategy aims to maintain a higher Hb. The most effective and safest strategy is unknown., Objectives: To determine the efficacy and safety of restrictive versus liberal RBC transfusion strategies for people diagnosed with haematological malignancies treated with intensive chemotherapy or radiotherapy, or both, with or without a haematopoietic stem cell transplant (HSCT)., Search Methods: We searched for randomised controlled trials (RCTs) and non-randomised studies (NRS) in MEDLINE (from 1946), Embase (from 1974), CINAHL (from 1982), Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2023, Issue 2), and eight other databases (including three trial registries) to 21 March 2023. We also searched grey literature and contacted experts in transfusion for additional trials. There were no language, date or publication status restrictions., Selection Criteria: We included RCTs and prospective NRS that evaluated restrictive versus liberal RBC transfusion strategies in children or adults with malignant haematological disorders receiving intensive chemotherapy or radiotherapy, or both, with or without HSCT., Data Collection and Analysis: Two authors independently screened references, full-text reports of potentially relevant studies, extracted data from the studies, and assessed the risk of bias. Any disagreement was discussed and resolved with a third review author. Dichotomous outcomes were presented as a risk ratio (RR) with a 95% confidence interval (CI). Narrative syntheses were used for heterogeneous outcome measures. Review Manager Web was used to meta-analyse the data. Main outcomes of interest included: all-cause mortality at 31 to 100 days, quality of life, number of participants with any bleeding, number of participants with clinically significant bleeding, serious infections, length of hospital admission (days) and hospital readmission at 0 to 3 months. The certainty of the evidence was assessed using GRADE., Main Results: Nine studies met eligibility; eight RCTs and one NRS. Six hundred and forty-four participants were included from six completed RCTs (n = 560) and one completed NRS (n = 84), with two ongoing RCTs consisting of 294 participants (260 adult and 34 paediatric) pending inclusion. Only one completed RCT included children receiving HSCT (n = 6); the other five RCTs only included adults: 239 with acute leukaemia receiving chemotherapy and 315 receiving HSCT (166 allogeneic and 149 autologous). The transfusion threshold ranged from 70 g/L to 80 g/L for restrictive and from 80 g/L to 120 g/L for liberal strategies. Effects were reported in the summary of findings tables only for the trials that included adults to reduce indirectness due to the limited evidence contributed by the prematurely terminated paediatric trial. Evidence from RCTs Overall, there may be little to no difference in the number of participants who die within 31 to 100 days using a restrictive compared to a liberal transfusion strategy, but the evidence is very uncertain (three studies; 451 participants; RR 1.00, 95% CI 0.27 to 3.70, P=0.99; very low-certainty evidence). There may be little to no difference in quality of life at 0 to 3 months using a restrictive compared to a liberal transfusion strategy, but the evidence is very uncertain (three studies; 431 participants; analysis unable to be completed due to heterogeneity; very low-certainty evidence). There may be little to no difference in the number of participants who suffer from any bleeding at 0 to 3 months using a restrictive compared to a liberal transfusion strategy (three studies; 448 participants; RR 0.91, 95% CI 0.78 to 1.06, P = 0.22; low-certainty evidence). There may be little to no difference in the number of participants who suffer from clinically significant bleeding at 0 to 3 months using a restrictive compared to a liberal transfusion strategy (four studies; 511 participants; RR: 0.94, 95% CI 0.74 to 1.19, P = 0.60; low-certainty evidence). There may be little to no difference in the number of participants who experience serious infections at 0 to 3 months using a restrictive compared to a liberal transfusion strategy (three studies, 451 participants; RR: 1.20, 95% CI 0.93 to 1.55, P = 0.17; low-certainty evidence). A restrictive transfusion strategy likely results in little to no difference in the length of hospital admission at 0 to 3 months compared to a liberal strategy (two studies; 388 participants; analysis unable to be completed due to heterogeneity in reporting; moderate-certainty evidence). There may be little to no difference between hospital readmission using a restrictive transfusion strategy compared to a liberal transfusion strategy (one study, 299 participants; RR: 0.89, 95% CI 0.52 to 1.50; P = 0.65; low-certainty evidence). Evidence from NRS The evidence is very uncertain whether a restrictive RBC transfusion strategy: reduces the risk of death within 100 days (one study, 84 participants, restrictive 1 death; liberal 1 death; very low-certainty evidence); or decreases the risk of clinically significant bleeding (one study, 84 participants, restrictive 3; liberal 8; very low-certainty evidence). No NRS reported on the other eligible outcomes., Authors' Conclusions: Findings from this review were based on seven studies and 644 participants. Definite conclusions are challenging given the relatively few included studies, low number of included participants, heterogeneity of intervention and outcome reporting, and overall certainty of evidence. To increase the certainty of the true effect of a restrictive RBC transfusion strategy on clinical outcomes, there is a need for rigorously designed and executed studies. The evidence is largely based on two populations: adults with acute leukaemia receiving intensive chemotherapy and adults with haematologic malignancy requiring HSCT. Despite the addition of 405 participants from three RCTs to the previous review's results, there is still insufficient evidence to answer this review's primary outcome. If we assume a mortality rate of 3% within 100 days, we would need a total of 1492 participants to have an 80% chance of detecting, at a 5% level of significance, an increase in all-cause mortality from 3% to 6%. Further RCTs are needed overall, particularly in children., (Copyright © 2024 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.)

Sleep medications often carry residual effects potentially affecting driving safety, warranting network meta-analysis (NMA). PubMed/EMBASE/TRID/Clinicaltrials.gov/WHO-ICTRP/WebOfScience were inquired for randomized controlled trials of hypnotic driving studies in persons with insomnia and healthy subjects up to 05/28/2023, considering the vehicle's standard deviation of lateral position - SDLP (Standardized Mean Difference/SMD) and driving impairment rates on the first morning (co-primary outcomes) and endpoint. Risk-of-bias, global/local inconsistencies were measured, and CINeMA was used to assess the confidence in the evidence. Of 4,805 identified records, 26 cross-over RCTs were included in the systematic review, of which 22 entered the NMA, focusing on healthy subjects only. After a single administration, most molecules paralleled the placebo, outperforming zopiclone regarding SDLP. In contrast, ramelteon 8 mg, daridorexant 100 mg, zolpidem 10 mg bedtime, zolpidem middle-of-the-night 10 mg and 20 mg, mirtazapine 15-30 mg, and triazolam 0.5 mg performed significantly worse than placebo. Lemborexant 2.5-5 mg, suvorexant 15-20 mg, and zolpidem 3.5 mg middle-of-the-night associated with lower impairment than zopiclone. Repeated administration (maximum follow-up time of ten days) caused fewer residual effects than acute ones, except for flurazepam. Heterogeneity and inconsistency were negligible. Confidence in the evidence was low/very low. Sensitivity analyses confirmed the main analyses. Most FDA-approved hypnotics overlapped placebo at in-label doses, outperforming zopiclone. Repeated administration for 15 days or less reduced residual effects, warranting further research on the matter., Competing Interests: Declaration of competing interest E.V. has received grants and served as consultant, advisor or CME speaker for the following entities: AB-Biotics, AbbVie, Adamed, Angelini, Biogen, Biohaven, Boehringer-Ingelheim, Celon Pharma, Compass, Dainippon Sumitomo Pharma, Ethypharm, Ferrer, Gedeon Richter, GH Research, Glaxo-Smith Kline, HMNC, Idorsia, Janssen, Lundbeck, Medincell, Merck, Novartis, Orion Corporation, Organon, Otsuka, Roche, Rovi, Sage, Sanofi-Aventis, Sunovion, Takeda, and Viatris, outside the submitted work. M.S. has received honoraria/has been a consultant for Angelini, Lundbeck, and Otsuka. M.F. served as a rater for Massachusetts General Hospital Clinical Trials Network and Institute, Boston, MA, USA, and its subsidiaries for the following entities. M.F. received honoraria from the American Society of Clinical Psychopharmacology (ASCP) for his speaker activities, and from Angelini, Lundbeck, Bristol Meyer Squibb, and Boehringer-Ingelheim. Ad.B. has received research support from Janssen, Lundbeck, and Otsuka and lecture fees for educational meeting from Chiesi, Lundbeck, Roche, Sunovion, Viatris, Recordati, Angelini and Takeda; he has served on advisory boards for Eli Lilly, Jansen, Lundbeck, Otsuka, Roche, and Takeda, Chiesi, Recordati, Angelini, Viatris. All other authors declare that they have no conflicts of interest., (Copyright © 2024 Elsevier B.V. and ECNP. All rights reserved.)

Introduction: Literature searches are routinely used by researchers for conducting systematic reviews as well as by healthcare providers, and sometimes patients, to quickly guide their clinical decisions. Using more than one database is generally recommended but may not always be necessary for some fields. This study aimed to determine the added value of searching additional databases beyond MEDLINE when conducting a literature search of hyperbaric oxygen treatment (HBOT) randomised controlled trials (RCTs)., Methods: This study consisted of two phases: a scoping review of all RCTs in the field of HBOT, followed by a a statistical analysis of sensitivity, precision, 'number needed to read' (NNR) and 'number unique' included by individual biomedical databases. MEDLINE, Embase, Cochrane Central Register of Control Trials (CENTRAL), and Cumulated Index to Nursing and Allied Health Literature (CINAHL) were searched without date or language restrictions up to December 31, 2022. Screening and data extraction were conducted in duplicate by pairs of independent reviewers. RCTs were included if they involved human subjects and HBOT was offered either on its own or in combination with other treatments., Results: Out of 5,840 different citations identified, 367 were included for analysis. CENTRAL was the most sensitive (87.2%) and had the most unique references (7.1%). MEDLINE had the highest precision (23.8%) and optimal NNR (four). Among included references, 14.2% were unique to a single database., Conclusions: Systematic reviews of RCTs in HBOT should always utilise multiple databases, which at minimum include MEDLINE, Embase, CENTRAL and CINAHL., (Copyright: This article is the copyright of the authors who grant Diving and Hyperbaric Medicine a non-exclusive licence to publish the article in electronic and other forms.)

A cluster randomized trial is defined as a randomized trial in which intact social units of individuals are randomized rather than individuals themselves. Outcomes are observed on individual participants within clusters (such as patients). Such a design allows assessing interventions targeting cluster-level participants (such as physicians), individual participants or both. Indeed, many interventions assessed in cluster randomized trials are actually complex ones, with distinct components targeting different levels. For a cluster-level intervention, cluster randomization is an obvious choice: the intervention is not divisible at the individual-level. For individual-level interventions, cluster randomization may nevertheless be suitable to prevent group contamination, for logistical reasons, to enhance participants' adherence, or when objectives pertain to the cluster level. An unacceptable reason for cluster randomization would be to avoid obtaining individual consent. Indeed, participants in cluster randomized trials have to be protected as in any type of trial design. Participants may be people from whom data are collected, but they may also be people who are intervened upon, and this includes both patients and physicians (for example, physicians receiving training interventions). Consent should be sought as soon as possible, although there may exist situations where participants may consent only for data collection, not for being exposed to the intervention (because, for instance, they cannot opt-out). There may even be situations where participants are not able to consent at all. In this latter situation a waiver of consent must be granted by a research ethics committee., (Copyright © 2024 Elsevier Masson SAS. All rights reserved.)

Background: Pragmatic trials aim to generate evidence to directly inform patient, caregiver and health-system manager policies and decisions. Heterogeneity in patient characteristics contributes to heterogeneity in their response to the intervention. However, there are many other sources of heterogeneity in outcomes. Based on the expertise and judgements of the authors, we identify different sources of clinical and methodological heterogeneity, which translate into heterogeneity in patient responses-some we consider as desirable and some as undesirable. For each of them, we discuss and, using real-world trial examples, illustrate how heterogeneity should be managed over the whole course of the trial., Main Text: Heterogeneity in centres and patients should be welcomed rather than limited. Interventions can be flexible or tailored and control interventions are expected to reflect usual care, avoiding use of a placebo. Co-interventions should be allowed; adherence should not be enforced. All these elements introduce heterogeneity in interventions (experimental or control), which has to be welcomed because it mimics reality. Outcomes should be objective and possibly routinely collected; standardised assessment, blinding and adjudication should be avoided as much as possible because this is not how assessment would be done outside a trial setting. The statistical analysis strategy must be guided by the objective to inform decision-making, thus favouring the intention-to-treat principle. Pragmatic trials should consider including process analyses to inform an understanding of the trial results. Needed data to conduct these analyses should be collected unobtrusively. Finally, ethical principles must be respected, even though this may seem to conflict with goals of pragmatism; consent procedures could be incorporated in the flow of care., (© 2022. The Author(s).)

Background: Use of patient-reported outcomes (PROs) and patient and public engagement are critical ingredients of pragmatic trials, which are intended to be patient centered. Engagement of patients and members of the public in selecting the primary trial outcome and determining the target difference can better ensure that the trial is designed to inform the decisions of those who ultimately stand to benefit. However, to the best of our knowledge, the use and reporting of PROs and patient and public engagement in pragmatic trials have not been described. The objectives of this study were to review a sample of pragmatic trials to describe (1) the prevalence of reporting patient and public engagement; (2) the prevalence and types of PROs used; (3) how its use varies across trial characteristics; and (4) how sample sizes and target differences are determined for trials with primary PROs., Methods and Findings: This was a methodological review of primary reports of pragmatic trials. We used a published electronic search filter in MEDLINE to identify pragmatic trials, published in English between January 1, 2014 and April 3, 2019; we identified the subset that were registered in ClinicalTrials.gov and explicitly labeled as pragmatic. Trial descriptors were downloaded from ClinicalTrials.gov; information about PROs and sample size calculations were extracted from the manuscript. Chi-squared, Cochran-Armitage, and Wilcoxon rank sum tests were used to examine associations between trial characteristics and use of PROs. Among 4,337 identified primary trial reports, 1,988 were registered in CT.gov, of which 415 were explicitly labeled as pragmatic. Use of patient and public engagement was identified in 39 (9.4%). PROs were measured in 235 (56.6%): 144 (34.7%) used PROs as primary outcomes and 91 (21.9%) as only secondary outcomes. Primary PROs were symptoms (64; 44%), health behaviors (36; 25.0%), quality of life (17; 11.8%), functional status (16; 11.1%), and patient experience (10; 6.9%). Trial characteristics with lower prevalence of use of PROs included being conducted exclusively in children or adults over age 65 years, cluster randomization, recruitment in low- and middle-income countries, and primary purpose of prevention; trials conducted in Europe had the highest prevalence of PROs. For the 144 trials with a primary PRO, 117 (81.3%) reported a sample size calculation for that outcome; of these, 71 (60.7%) justified the choice of target difference, most commonly, using estimates from pilot studies (31; 26.5%), standardized effect sizes (20; 17.1%), or evidence reviews (16; 13.7%); patient or stakeholder opinions were used to justify the target difference in 8 (6.8%). Limitations of this study are the need for trials to be registered in ClinicalTrials.gov, which may have reduced generalizability, and extracting information only from the primary trial report., Conclusions: In this study, we observed that pragmatic trials rarely report patient and public engagement and do not commonly use PROs as primary outcomes. When provided, target differences are often not justified and rarely informed by patients and stakeholders. Research funders, scientific journals, and institutions should support trialists to incorporate patient engagement to fulfill the mandate of pragmatic trials to be patient centered., Competing Interests: The authors have declared that no competing interests exist.

Objective: To describe characteristics of randomized controlled trials (RCTs) conducted using electronic health records (EHRs), including completeness and transparency of reporting assessed against the 2021 CONSORT Extension for RCTs Conducted Using Cohorts and Routinely Collected Data (CONSORT-ROUTINE) criteria., Study Design: MEDLINE and Cochrane Methodology Register were searched for a sample of RCTs published from 2011-2018. Completeness of reporting was assessed in a random sample using a pre-defined coding form., Results: Of the 183 RCT publications identified, 122 (67%) used EHRs to identify eligible participants, 139 (76%) used the EHR as part of the intervention and 137 (75%) to ascertain outcomes. When 60 publications were evaluated against the CONSORT 2010 item and the corresponding extension for the 8 modified items, four items were 'adequately reported' for most trials. Five new reporting items were identified for the CONSORT-ROUTINE extension; when evaluated, one was 'adequately reported', three were reported 'inadequately or not at all', the other 'partially'. There were, however, some encouraging signs with adequate and partial reporting of many important items, including descriptions of trial design, the consent process, outcome ascertainment and interpretation., Conclusion: Aspects of RCTs using EHRs are sub-optimally reported. Uptake of the CONSORT-ROUTINE Extension may improve reporting., (Copyright © 2021. Published by Elsevier Inc.)

Background: Incorporating cluster randomized trials (CRTs) into meta-analyses is challenging because appropriate standard errors of study estimates accounting for clustering are not always reported. Systematic reviews of CRTs often use a single constant external estimate of the intraclass correlation coefficient (ICC) to adjust study estimate standard errors and facilitate meta-analyses; an approach that fails to account for possible variation of ICCs among studies and the imprecision with which they are estimated. Using a large systematic review of the effects of diabetes quality improvement interventions, we investigated whether we could better account for ICC variation and uncertainty in meta-analyzed effect estimates by imputing missing ICCs from a posterior predictive distribution constructed from a database of relevant ICCs., Methods: We constructed a dataset of ICC estimates from applicable studies. For outcomes with two or more available ICC estimates, we constructed posterior predictive ICC distributions in a Bayesian framework. For a selected continuous outcome, glycosylated hemoglobin (HbA1c), we compared the impact of incorporating a single constant ICC versus imputing ICCs drawn from the posterior predictive distribution when estimating the effect of intervention components on post treatment mean in a case study of diabetes quality improvement trials., Results: Using internal and external ICC estimates, we were able to construct a database of 59 ICCs for 12 of the 13 review outcomes (range 1-10 per outcome) and estimate the posterior predictive ICC distribution for 11 review outcomes. Synthesized results were not markedly changed by our approach for HbA1c., Conclusion: Building posterior predictive distributions to impute missing ICCs is a feasible approach to facilitate principled meta-analyses of cluster randomized trials using prior data. Further work is needed to establish whether the application of these methods leads to improved review inferences for different reviews based on different factors (e.g., proportion of CRTs and CRTs with missing ICCs, different outcomes, variation and precision of ICCs)., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Objectives: To describe the prevalence of risks of bias in cluster-randomized trials of individual-level interventions, according to the Cochrane Risk of Bias tool., Study Design and Setting: Review undertaken in duplicate of a random sample of 40 primary reports of cluster-randomized trials of individual-level interventions., Results: The most common reported reasons for adopting cluster randomization were the need to avoid contamination (17, 42.5%) and practical considerations (14, 35%). Of the 40 trials all but one was assessed as being at risk of bias. A majority (27, 67.5%) were assessed as at risk due to the timing of identification and recruitment of participants; many (21, 52.5%) due to an apparent lack of adequate allocation concealment; and many due to selectively reported results (22, 55%), arising from a mixture of reasons including lack of documentation of primary outcome. Other risks mostly occurred infrequently., Conclusion: Many cluster-randomized trials evaluating individual-level interventions appear to be at risk of bias, mostly due to identification and recruitment biases. We recommend that investigators carefully consider the need for cluster randomization; follow recommended procedures to mitigate risks of identification and recruitment bias; and adhere to good reporting practices including clear documentation of primary outcome and allocation concealment methods., (Copyright © 2021. Published by Elsevier Inc.)

Objective: To assess the reporting quality of randomized controlled trials (RCTs) with multicenter design, particularly whether necessary information related to multicenter characteristics was adequately reported., Study Design and Setting: Through a search of 4 international electronic databases, we identified multicenter RCTs published in English from 1975 to 2019. Reporting quality was assessed by the CONSORT (Consolidated Standards of Reporting Trials) checklist (37 items) and by a self-designed multicenter-specific checklist (27 items covering multicenter design, implement and analysis). The scores of trials published in three time periods (1975-1995; 1996-2009; and 2010-2019) were also compared., Results: A total of 2,844 multicenter RCTs were included. For the CONSORT checklist, the mean (standard deviation) reporting score was 24.1 (5.5), 12 items were assessed as excellent (>90%), 12 items as good (50%-90%), and 13 items as poor (<50%). For the multicenter checklist, the reporting score was 3.9 (2.2), only 3 items were excellent or good, and the remaining 24 items were poor. Time period comparison showed that reporting quality improved over time, especially after the CONSORT 2010 issued., Conclusion: Although CONSORT appears to have enhanced the reporting quality of multicenter RCTs, further improvement is needed. A "CONSORT extension for multicenter trials" should be developed., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Competing Interests: Competing interests: We have read and understood BMJ policy on declaration of interests and declare the following interests: JH, RW, and JAK have no competing interests to declare; DM developed the CONSORT and PRISMA statements and has been involved in the development of other reporting guidelines.

Background: Recruitment and engagement of clusters in a cluster randomized controlled trial can sometimes prove challenging. Identification of successful or unsuccessful strategies may be beneficial in guiding future researchers in conducting their cluster randomized controlled trial. This study aimed to identify strategies that could be used to facilitate the delivery of cluster randomized controlled trials in hospitals., Methods: The study employed the Consolidated Framework for Implementation Research-Expert Recommendations for Implementing Change matching tool. The barriers and enablers to cluster randomized controlled trial conduct identified in our previously conducted studies served as a means of determinant identification for the conduct of cluster randomized controlled trials. These determinants were mapped to Consolidated Framework for Implementation Research constructs and then matched to Expert Recommendations for Implementing Change compilation strategies using the Consolidated Framework for Implementation Research-Expert Recommendations for Implementing Change matching tool., Results: The Expert Recommendations for Implementing Change strategies matched to at least one determinant Consolidated Framework for Implementation Research construct were as follows: (1) 'Identify and prepare champions', (2) 'Conduct local needs assessment', (3) 'Conduct educational meetings', (4) 'Inform local opinion leaders', (5) 'Build a coalition', (6) 'Promote adaptability', (7) 'Develop a formal implementation blueprint', (8) 'Involve patients/consumers and family members', (9) 'Obtain and use patients/consumers and family feedback', (10) 'Develop educational materials', (11) 'Promote network weaving', (12) 'Distribute educational materials', (13) 'Access new funding' and (14) 'Develop academic partnerships'., Conclusion: This study was intended as a step in the research agenda aimed at facilitating cluster randomized controlled trial delivery in hospitals and can act as a resource for future researchers when planning their cluster randomized controlled trial, with the expectation that the strategies identified here will be tailored to each context.

Importance: Extenuating circumstances can trigger unplanned changes to randomized trials and introduce methodological, ethical, feasibility, and analytical challenges that can potentially compromise the validity of findings. Numerous randomized trials have required changes in response to the COVID-19 pandemic, but guidance for reporting such modifications is incomplete., Objective: As a joint extension for the CONSORT and SPIRIT reporting guidelines, CONSERVE (CONSORT and SPIRIT Extension for RCTs Revised in Extenuating Circumstances) aims to improve reporting of trial protocols and completed trials that undergo important modifications in response to extenuating circumstances., Evidence: A panel of 37 international trial investigators, patient representatives, methodologists and statisticians, ethicists, funders, regulators, and journal editors convened to develop the guideline. The panel developed CONSERVE following an accelerated, iterative process between June 2020 and February 2021 involving (1) a rapid literature review of multiple databases (OVID Medline, OVID EMBASE, and EBSCO CINAHL) and gray literature sources from 2003 to March 2021; (2) consensus-based panelist meetings using a modified Delphi process and surveys; and (3) a global survey of trial stakeholders., Findings: The rapid review yielded 41 673 citations, of which 38 titles were relevant, including emerging guidance from regulatory and funding agencies for managing the effects of the COVID-19 pandemic on trials. However, no generalizable guidance for all circumstances in which trials and trial protocols might face unanticipated modifications were identified. The CONSERVE panel used these findings to develop a consensus reporting guidelines following 4 rounds of meetings and surveys. Responses were received from 198 professionals from 34 countries, of whom 90% (n = 178) indicated that they understood the concept definitions and 85.4% (n = 169) indicated that they understood and could use the implementation tool. Feedback from survey respondents was used to finalize the guideline and confirm that the guideline's core concepts were applicable and had utility for the trial community. CONSERVE incorporates an implementation tool and checklists tailored to trial reports and trial protocols for which extenuating circumstances have resulted in important modifications to the intended study procedures. The checklists include 4 sections capturing extenuating circumstances, important modifications, responsible parties, and interim data analyses., Conclusions and Relevance: CONSERVE offers an extension to CONSORT and SPIRIT that could improve the transparency, quality, and completeness of reporting important modifications to trials in extenuating circumstances such as COVID-19.

Cluster randomization results in an increase in sample size compared to individual randomization, referred to as an efficiency loss. This efficiency loss is typically presented under an assumption of no contamination in the individually randomized trial. An alternative comparator is the sample size needed under individual randomization to detect the attenuated treatment effect due to contamination. A general framework is provided for determining the extent of contamination that can be tolerated in an individually randomized trial before a cluster randomized design yields a larger sample size. Results are presented for a variety of cluster trial designs including parallel arm, stepped-wedge and cluster crossover trials. Results reinforce what is expected: individually randomized trials can tolerate a surprisingly large amount of contamination before they become less efficient than cluster designs. We determine the point at which the contamination means an individual randomized design to detect an attenuated effect requires a larger sample size than cluster randomization under a nonattenuated effect. This critical rate is a simple function of the design effect for clustering and the design effect for multiple periods as well as design effects for stratification or repeated measures under individual randomization. These findings are important for pragmatic comparisons between a novel treatment and usual care as any bias due to contamination will only attenuate the true treatment effect. This is a bias that operates in a predictable direction. Yet, cluster randomized designs with post-randomization recruitment without blinding, are at high risk of bias due to the differential recruitment across treatment arms. This sort of bias operates in an unpredictable direction. Thus, with knowledge that cluster randomized trials are generally at a greater risk of biases that can operate in a nonpredictable direction, results presented here suggest that even in situations where there is a risk of contamination, individual randomization might still be the design of choice., (© 2021 The Authors. Statistics in Medicine published by John Wiley & Sons Ltd.)

Importance: Randomized clinical trials (RCTs) provide the highest level of evidence to evaluate 2 or more surgical interventions. Surgical RCTs, however, face unique challenges in design and implementation., Objective: To evaluate the design, conduct, and reporting of contemporary surgical RCTs., Evidence Review: A literature search performed in the 2 journals with the highest impact factor in general medicine as well as 6 key surgical specialties was conducted to identify RCTs published between 2008 and 2020. All RCTs describing a surgical intervention in both experimental and control arms were included. The quality of included data was assessed by establishing an a priori protocol containing all the details to extract. Trial characteristics, fragility index, risk of bias (Cochrane Risk of Bias 2 Tool), pragmatism (Pragmatic Explanatory Continuum Indicator Summary 2 [PRECIS-2]), and reporting bias were assessed., Findings: A total of 388 trials were identified. Of them, 242 (62.4%) were registered; discrepancies with the published protocol were identified in 81 (33.5%). Most trials used superiority design (329 [84.8%]), and intention-to-treat as primary analysis (221 [56.9%]) and were designed to detect a large treatment effect (50.0%; interquartile range [IQR], 24.7%-63.3%). Only 123 trials (31.7%) used major clinical events as the primary outcome. Most trials (303 [78.1%]) did not control for surgeon experience; only 17 trials (4.4%) assessed the quality of the intervention. The median sample size was 122 patients (IQR, 70-245 patients). The median follow-up was 24 months (IQR, 12.0-32.0 months). Most trials (211 [54.4%]) had some concern of bias and 91 (23.5%) had high risk of bias. The mean (SD) PRECIS-2 score was 3.52 (0.65) and increased significantly over the study period. Most trials (212 [54.6%]) reported a neutral result; reporting bias was identified in 109 of 211 (51.7%). The median fragility index was 3.0 (IQR, 1.0-6.0). Multiplicity was detected in 175 trials (45.1%), and only 35 (20.0%) adjusted for multiple comparisons., Conclusions and Relevance: In this systematic review, the size of contemporary surgical trials was small and the focus was on minor clinical events. Trial registration remained suboptimal and discrepancies with the published protocol and reporting bias were frequent. Few trials controlled for surgeon experience or assessed the quality of the intervention.

Objectives: To estimate the prevalence of time-to-event (TTE) outcomes in cluster randomized trials (CRTs) and to examine their statistical management., Study Design and Setting: We searched PubMed to identify primary reports of CRTs published in six major general medical journals (2013-2018). Nature of outcomes and, for TTE outcomes, statistical methods for sample size, analysis, and measures of intracluster correlation were extracted., Results: A TTE analysis was used in 17% of the CRTs (32/184) either as a primary or secondary outcome analysis, or in a sensitivity analysis. Among the five CRTs with a TTE primary outcome, two accounted for both intracluster correlation and the TTE nature of the outcome in sample size calculation; one reported a measure of intracluster correlation in the analysis. Among the 32 CRTs with a least one TTE analysis, 44% (14/32) accounted for clustering in all TTE analyses. We identified 12 additional CRTs in which there was at least one outcome not analyzed as TTE for which a TTE analysis might have been preferred., Conclusion: TTE outcomes are not uncommon in CRTs but appropriate statistical methods are infrequently used. Our results suggest that further methodological development and explicit recommendations for TTE outcomes in CRTs are needed., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Evaluating whether an intervention works when trialled in groups of individuals can pose complex challenges for clinical research. Cluster randomised controlled trials involve the random allocation of groups or clusters of individuals to receive an intervention, and they are commonly used in global health research. In this paper, we describe the potential reasons for the increasing popularity of cluster trials in low-income and middle-income countries. We also draw on key areas of global health research for an assessment of common trial planning practices, and we address their methodological shortcomings and pitfalls. Lastly, we discuss alternative approaches for population-level intervention trials that could be useful for research undertaken in low-income and middle-income countries for situations in which the use of cluster randomisation might not be appropriate., (Copyright © 2021 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

Many randomized controlled trials (RCTs) are biased and difficult to reproduce due to methodological flaws and poor reporting. There is increasing attention for responsible research practices and implementation of reporting guidelines, but whether these efforts have improved the methodological quality of RCTs (e.g., lower risk of bias) is unknown. We, therefore, mapped risk-of-bias trends over time in RCT publications in relation to journal and author characteristics. Meta-information of 176,620 RCTs published between 1966 and 2018 was extracted. The risk-of-bias probability (random sequence generation, allocation concealment, blinding of patients/personnel, and blinding of outcome assessment) was assessed using a risk-of-bias machine learning tool. This tool was simultaneously validated using 63,327 human risk-of-bias assessments obtained from 17,394 RCTs evaluated in the Cochrane Database of Systematic Reviews (CDSR). Moreover, RCT registration and CONSORT Statement reporting were assessed using automated searches. Publication characteristics included the number of authors, journal impact factor (JIF), and medical discipline. The annual number of published RCTs substantially increased over 4 decades, accompanied by increases in authors (5.2 to 7.8) and institutions (2.9 to 4.8). The risk of bias remained present in most RCTs but decreased over time for allocation concealment (63% to 51%), random sequence generation (57% to 36%), and blinding of outcome assessment (58% to 52%). Trial registration (37% to 47%) and the use of the CONSORT Statement (1% to 20%) also rapidly increased. In journals with a higher impact factor (>10), the risk of bias was consistently lower with higher levels of RCT registration and the use of the CONSORT Statement. Automated risk-of-bias predictions had accuracies above 70% for allocation concealment (70.7%), random sequence generation (72.1%), and blinding of patients/personnel (79.8%), but not for blinding of outcome assessment (62.7%). In conclusion, the likelihood of bias in RCTs has generally decreased over the last decades. This optimistic trend may be driven by increased knowledge augmented by mandatory trial registration and more stringent reporting guidelines and journal requirements. Nevertheless, relatively high probabilities of bias remain, particularly in journals with lower impact factors. This emphasizes that further improvement of RCT registration, conduct, and reporting is still urgently needed., Competing Interests: The authors have declared that no competing interests exist.

Background: Serious concerns regarding quality of conduct and reporting of noninferiority trials (NITs) have been raised. Systematic analysis of the quality of the surgical NITs is lacking. Assessing the quality of conduct, reporting, and interpretation of surgical NITs in cancer patients is critical given their potential clinical impact. We aim to assess the quality of conduct, reporting, and interpretation of NITs that investigate the effects of surgical management in cancer patients., Methods: A cross-sectional analysis of papers identified through a comprehensive literature database search was performed. Forty papers employing a phase III noninferiority (NI) randomized trial design to study effects of surgical methodology or sequencing of surgery in patients with solid cancers were included. Papers were assessed for type of analysis, justification of the noninferiority margin (NIM), consistency of type I error with confidence intervals (CIs), ability to achieve the predefined sample size, and interpretations regarding NI., Results: Only half of the papers used both intention-to-treat and per protocol analyses; 62.5% provided no or poor justification for the NIM; 42.5% showed inconsistency of the type I error rate with CIs; 52.5% were deemed poor or fair quality, and 60.0% did not achieve the predefined sample size. One-fifth of the papers provided interpretation of the NI hypothesis that was not in concordance with the CONSORT guidelines., Conclusions: The quality of conduct, reporting, and interpretation of surgical NITs is suboptimal, requiring further improvements through adherence to guidelines and rigorous assessment at the stages of the study approval, funding, and the peer-review process.

Objectives: Over 400 reporting guidelines are currently published, but the frequency of their use by authors to accurately and transparently report research remains unclear. This study examined citation counts of reporting guidelines and characteristics contributing to their citation impact., Study Design and Setting: Web of Science database was searched for citation counts of all reporting guidelines with a minimum citation age of 5 years. The total citation impact, mean citation impact and the factors contributing to 2- and 5-year citation rate were established., Results: The search identified 296 articles of reporting guidelines from 1995 to 2013. The mean citations per year was 32.4 (95% confidence interval, 22.3-42.4 citations). The factors associated with 2- and 5-year citation performance of reporting guidelines included the following: open access to the reporting guideline, field of the publishing journal (general vs. specialized medical journal), impact factor of the publishing journal, simultaneous publication in multiple journals, and a male first author., Conclusion: The citation rate across reporting guidelines varied with journal impact factor, open access publication, field of the publishing journal, simultaneous publications, and a male first author. Gaps in citations highlight opportunities to increase visibility and encourage author use of reporting guidelines., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Individual-cluster trials randomize groups of individuals but deliver study interventions directly to individual participants. We examine three arguments that might justify the perception that the bar for a waiver of consent should be lower in such trials than for individually randomized trials. We contend that if these arguments are treated as sufficient to grant a waiver of consent, then a loophole emerges in research oversight. Such loopholes are morally hazardous for study participants, the integrity of science, and public trust in the research enterprise. We conclude by articulating the standards that research ethics committees should use to evaluate requests for waivers of consent in individual-cluster trials., (© 2020 by The Hastings Center. All rights reserved.)

Objectives: To explore whether trial population characteristics modify treatment responses across various interventions, comparators and rheumatic conditions., Methods: In this meta-epidemiological study, we included trials from systematic reviews available from the Cochrane Musculoskeletal Group published up to 23 April 2019 in Cochrane Library with meta-analyses of five or more randomised controlled trials (RCTs) published from year 2000. From trial reports, we extracted data on 20 population characteristics. For characteristics with sufficient data (ie, available for ≥2/3 of the trials), we performed multilevel meta-epidemiological analyses., Results: We identified 19 eligible systematic reviews contributing 187 RCTs (212 comparisons). Only age and sex were explicitly reported in ≥2/3 of the trials. Using information about the country of the trials led to sufficient data for five further characteristics, that is, 7 out of 20 (35%) protocolised characteristics were analysed. The meta-regressions showed effect modification by economic status, place of residence, and, nearly, from healthcare system (explaining 4.8%, 0.9% and 1.5% of the between-trial variation, respectively). No effect modification was demonstrated from age, sex, patient education/health literacy or predominant religion., Conclusions: This study demonstrates the scarce reporting of most population characteristics, hampering investigation of their impact with meta-research. Our sparse results suggest that place of residence (ie, continent of the trial), economic status (based on World Bank classifications) and healthcare system (based on WHO index for health system performance) may be important in explaining the variation in treatment response across trials. There is an urgent need for consistent reporting of important population characteristics in trials., Prospero Registration Number: CRD42019127642., Competing Interests: Competing interests: MdW reports personal fees from Abbvie, through Stichting Tools; personal fees from BMS; personal fees from Celgene; personal fees from Lilly; personal fees from Novartis; personal fees from Pfizer; personal fees from Roche; from outside the submitted work. AB holds a research grant from Abbvie and received honoraria for participation in advisory boards from Lilly and Galapagos. All compensations were paid to the department., (© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

The CONSORT 2010 statement provides minimum guidelines for reporting randomized trials. Its widespread use has been instrumental in ensuring transparency in the evaluation of new interventions. More recently, there has been a growing recognition that interventions involving artificial intelligence (AI) need to undergo rigorous, prospective evaluation to demonstrate impact on health outcomes. The CONSORT-AI (Consolidated Standards of Reporting Trials-Artificial Intelligence) extension is a new reporting guideline for clinical trials evaluating interventions with an AI component. It was developed in parallel with its companion statement for clinical trial protocols: SPIRIT-AI (Standard Protocol Items: Recommendations for Interventional Trials-Artificial Intelligence). Both guidelines were developed through a staged consensus process involving literature review and expert consultation to generate 29 candidate items, which were assessed by an international multi-stakeholder group in a two-stage Delphi survey (103 stakeholders), agreed upon in a two-day consensus meeting (31 stakeholders) and refined through a checklist pilot (34 participants). The CONSORT-AI extension includes 14 new items that were considered sufficiently important for AI interventions that they should be routinely reported in addition to the core CONSORT 2010 items. CONSORT-AI recommends that investigators provide clear descriptions of the AI intervention, including instructions and skills required for use, the setting in which the AI intervention is integrated, the handling of inputs and outputs of the AI intervention, the human-AI interaction and provision of an analysis of error cases. CONSORT-AI will help promote transparency and completeness in reporting clinical trials for AI interventions. It will assist editors and peer reviewers, as well as the general readership, to understand, interpret and critically appraise the quality of clinical trial design and risk of bias in the reported outcomes.

Objectives: Identifying pragmatic trials from among all randomized trials is challenging because of inconsistent reporting. Our objective was to develop and validate a search filter to identify reports of pragmatic trials from Ovid MEDLINE., Study Design and Setting: Two sets of known and probable pragmatic trial records were analyzed using text mining to generate candidate terms. Two large population sets comprising clinical trials and explanatory trials were used to select discriminating terms. Various combinations of terms were tested iteratively to achieve optimal search performance. Two externally derived sets were used to validate sensitivity and specificity of the derived filters., Results: Our validated sensitivity-maximizing filter (combines trial design terms with terms relating to attributes of pragmatic trials) retrieves over 42,000 records in MEDLINE and has sensitivity of 46.4% (95% confidence interval (CI) 37.2 to 55.7%) and estimated specificity of 98.1% (95% CI 93.4 to 99.8%). Search performance is superior to other ad hoc filters for pragmatic trials. The Cochrane search for randomized trials has much better sensitivity (98.2%), but poorer specificity (1.9%) and retrieves 4.5 million records., Conclusion: A highly specific filter (low false positive rate) with moderate sensitivity is available for identifying reports of trials more likely to be pragmatic., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Objectives: This study aimed to assess if the Consolidated Standards of Reporting Trials (CONSORT) endorsement by journals is associated with improved completeness of reporting of randomized clinical trials (RCTs) in dentistry., Study Design and Setting: We searched for RCTs in dentistry indexed/published on PubMed in 2017. Study selection was undertaken by two reviewers independently. Data related to the general characteristics, reports of methodological characteristics, and whether the trial report was published in a journal that endorses the CONSORT Statement were extracted by two reviewers. Descriptive statistics were used to present the data surrounding the general and methodological characteristics of the included studies. We explored differences in the reporting of 12 methodological items between journals that endorsed CONSORT and those that did not., Results: Five hundred and thirty three reports were included. The main area was implant dentistry with 101 articles (18.9%). Most studies had a parallel design (75.8%), performed at a single center (89.3%) and presenting two groups of comparison (75.6%). The median number of sample size was 50 (interquartile range: 31-90). Six of the 12 methodologic items were reported more often for RCTs published in journals that endorsed CONSORT than in journals that did not., Conclusion: CONSORT endorsement by journals is linked to improvement in the quality of RCT reports in dentistry., (Copyright © 2020 Elsevier Inc. All rights reserved.)

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., (© The Author(s) 2020. Published by Oxford University Press on behalf of the International Epidemiological Association.)

Background: Novel rationales for randomizing clusters rather than individuals appear to be emerging from the push for more pragmatic trials, for example, to facilitate trial recruitment, reduce the costs of research, and improve external validity. Such rationales may be driven by a mistaken perception that choosing cluster randomization lessens the need for informed consent. We reviewed a random sample of published cluster randomized trials involving only individual-level health care interventions to determine (a) the prevalence of reporting a rationale for the choice of cluster randomization; (b) the types of explicit, or if absent, apparent rationales for the use of cluster randomization; (c) the prevalence of reporting patient informed consent for study interventions; and (d) the types of justifications provided for waivers of consent. We considered cluster randomized trials for evaluating exclusively the individual-level health care interventions to focus on clinical trials where individual randomization is only theoretically possible and where there is a general expectation of informed consent., Methods: A random sample of 40 cluster randomized trials were identified by implementing a validated electronic search filter in two electronic databases (Ovid MEDLINE and Embase), with two reviewers independently extracting information from each trial. Inclusion criteria were the following: primary report of a cluster randomized trial, evaluating exclusively an individual-level health care intervention, published between 2007 and 2016, and conducted in Canada, the United States, European Union, Australia, or low- and middle-income country settings., Results: Twenty-five trials (62.5%, 95% confidence interval = 47.5%-77.5%) reported an explicit rationale for the use of cluster randomization. The most commonly reported rationales were those with logistical or administrative convenience (15 trials, 60%) and those that need to avoid contamination (13 trials, 52%); five trials (20%) were cited rationales related to the push for more pragmatic trials. Twenty-one trials (52.5%, 95% confidence interval = 37%-68%) reported written informed consent for the intervention, two (5%) reported verbal consent, and eight (20%) reported waivers of consent, while in nine trials (22.5%) consent was unclear or not mentioned. Reported justifications for waivers of consent included that study interventions were already used in clinical practice, patients were not randomized individually, and the need to facilitate the pragmatic nature of the trial. Only one trial reported an explicit and appropriate justification for waiver of consent based on minimum criteria in international research ethics guidelines, namely, infeasibility and minimal risk., Conclusion: Rationales for adopting cluster over individual randomization and for adopting consent waivers are emerging, related to the need to facilitate pragmatic trials. Greater attention to clear reporting of study design rationales, informed consent procedures, as well as justification for waivers is needed to ensure that such trials meet appropriate ethical standards.

The stepped-wedge cluster randomized trial (SW-CRT) involves the sequential transition of clusters (such as hospitals, public health units or communities) from control to intervention conditions in a randomized order. The use of the SW-CRT is growing rapidly. Yet the SW-CRT is at greater risks of bias compared with the conventional parallel cluster randomized trial (parallel-CRT). For this reason, the CONSORT extension for SW-CRTs requires that investigators provide a clear justification for the choice of study design. In this paper, we argue that all other things being equal, the SW-CRT is at greater risk of bias due to misspecification of the secular trends at the analysis stage. This is particularly problematic for studies randomizing a small number of heterogeneous clusters. We outline the potential conditions under which an SW-CRT might be an appropriate choice. Potentially appropriate and often overlapping justifications for conducting an SW-CRT include: (i) the SW-CRT provides a means to conduct a randomized evaluation which otherwise would not be possible; (ii) the SW-CRT facilitates cluster recruitment as it enhances the acceptability of a randomized evaluation either to cluster gatekeepers or other stakeholders; (iii) the SW-CRT is the only feasible design due to pragmatic and logistical constraints (for example the roll-out of a scare resource); and (iv) the SW-CRT has increased statistical power over other study designs (which will include situations with a limited number of clusters). As the number of arguments in favour of an SW-CRT increases, the likelihood that the benefits of using the SW-CRT, as opposed to a parallel-CRT, outweigh its risks also increases. We argue that the mere popularity and novelty of the SW-CRT should not be a factor in its adoption. In situations when a conventional parallel-CRT is feasible, it is likely to be the preferred design., (© The Author(s) 2020. Published by Oxford University Press on behalf of the International Epidemiological Association.)

Background: The randomized controlled trial (RCT) is considered the gold standard study design to inform decisions about the effectiveness of interventions. However, a common limitation is inadequate reporting of the applicability of the intervention and trial results for people who are "socially disadvantaged" and this can affect policy-makers' decisions. We previously developed a framework for identifying health-equity-relevant trials, along with a reporting guideline for transparent reporting. In this study, we provide a descriptive assessment of health-equity considerations in 200 randomly sampled equity-relevant trials., Methods: We developed a search strategy to identify health-equity-relevant trials published between 2013 and 2015. We randomly sorted the 4316 records identified by the search and screened studies until 100 individually randomized (RCTs) and 100 cluster randomized controlled trials (CRTs) were identified. We developed and pilot-tested a data extraction form based on our initial work, to inform the development of our reporting guideline for equity-relevant randomized trials., Results: In total, 39 trials (20%) were conducted in a low- and middle-income country and 157 trials (79%) in a high-income country focused on socially disadvantaged populations (78% CRTs, 79% RCTs). Seventy-four trials (37%) reported a subgroup analysis across a population characteristic associated with disadvantage (25% CRT, 49% RCTs), with 19% of included studies reporting subgroup analyses across sex, 9% across race/ethnicity/culture, and 4% across socioeconomic status. No subgroup analyses were reported for place of residence, occupation, religion, education, or social capital. One hundred and forty-one trials (71%) discussed the applicability of their results to one or more socially disadvantaged populations (68% of CRT, 73% of RCT)., Discussion: In this set of trials, selected for their relevance to health equity, data that were disaggregated for socially disadvantaged populations were rarely reported. We found that even when the data are available, opportunities to analyze health-equity considerations are frequently missed. The recently published equity extension of the Consolidated Reporting Standards for Randomized Trials (CONSORT-Equity) may help improve delineation of hypotheses related to socially disadvantaged populations, and transparency and completeness of reporting of health-equity considerations in RCTs. This study can serve as a baseline assessment of the reporting of equity considerations.

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.

Introduction: Transparent and accurate reporting is essential for readers to adequately interpret the results of a study. Journals can play a vital role in improving the reporting of published randomised controlled trials (RCTs). We describe an RCT to evaluate our hypothesis that asking peer reviewers to check whether the most important and poorly reported CONsolidated Standards of Reporting Trials (CONSORT) items are adequately reported will result in higher adherence to CONSORT guidelines in published RCTs., Methods and Analysis: Manuscripts presenting the primary results of RCTs submitted to participating journals will be randomised to either the intervention group (peer reviewers will receive a reminder and short explanation of the 10 most important and poorly reported CONSORT items; they will be asked to check if these items are reported in the submitted manuscript) or a control group (usual journal practice). The primary outcome will be the mean proportion of the 10 items that are adequately reported in the published articles. Peer reviewers and manuscript authors will not be informed of the study hypothesis, design or intervention. Outcomes will be assessed in duplicate from published articles by two data extractors (at least one blinded to the intervention). We will enrol eligible manuscripts until a minimum of 83 articles per group (166 in total) are published., Ethics and Dissemination: This pragmatic RCT was approved by the Medical Sciences Interdivisional Research Ethics Committee of the University of Oxford (R62779/RE001). If this intervention is effective, it could be implemented by all medical journals without requiring large additional resources at journal level. Findings will be disseminated through presentations in relevant conferences and peer-reviewed publications. This trial is registered on the Open Science Framework (https://osf.io/c4hn8)., Competing Interests: Competing interests, and roles of the steering committee: SS is employed by the British Medical Journal (BMJ). IP and AC are employed by the Public Library of Science. DM, SH and IB are members of the CONsolidated Standards for Reporting Trials (CONSORT) executive and authors of the CONSORT 2010 statement. DM and PR are members of the EQUATOR (Enhancing the Quality and Transparency of Research) network steering group. MMS is a meta-researcher and reporting guideline developer, enthusiast and disseminator; he may therefore overestimate the importance of this project. All authors have declared that no other competing interests exist: the principal investigator (BS) is responsible for the preparation and the revisions of the study protocol, organising meetings of the steering committee, recruiting and randomising eligible manuscripts as well as the publication of study reports. The steering committee (IB, MB, SH, DM, PR, BS, MMS and SS) is responsible for revising the protocol, defining and validating the additional short explanation for each CONSORT item, advising on study implementation and for publishing the results of this study. MMS is responsible for the sample size calculation and the statistical analyses., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY. Published by BMJ.)