Characteristics, Progression, and Output of Randomized Platform Trials: A Systematic Review

Importance

Platform trials have become increasingly common, and evidence is needed to determine how this trial design is actually applied in current research practice.

Objective

To determine the characteristics, progression, and output of randomized platform trials.

Evidence Review

In this systematic review of randomized platform trials, Medline, Embase, Scopus, trial registries, gray literature, and preprint servers were searched, and citation tracking was performed in July 2022. Investigators were contacted in February 2023 to confirm data accuracy and to provide updated information on the status of platform trial arms. Randomized platform trials were eligible if they explicitly planned to add or drop arms. Data were extracted in duplicate from protocols, publications, websites, and registry entries. For each platform trial, design features such as the use of a common control arm, use of nonconcurrent control data, statistical framework, adjustment for multiplicity, and use of additional adaptive design features were collected. Progression and output of each platform trial were determined by the recruitment status of individual arms, the number of arms added or dropped, and the availability of results for each intervention arm.

Findings

The search identified 127 randomized platform trials with a total of 823 arms; most trials were conducted in the field of oncology (57 [44.9%]) and COVID-19 (45 [35.4%]). After a more than twofold increase in the initiation of new platform trials at the beginning of the COVID-19 pandemic, the number of platform trials has since declined. Platform trial features were often not reported (not reported: nonconcurrent control, 61 of 127 [48.0%]; multiplicity adjustment for arms, 98 of 127 [77.2%]; statistical framework, 37 of 127 [29.1%]). Adaptive design features were only used by half the studies (63 of 127 [49.6%]). Results were available for 65.2% of closed arms (230 of 353). Premature closure of platform trial arms due to recruitment problems was infrequent (5 of 353 [1.4%]).

Conclusions and Relevance

This systematic review found that platform trials were initiated most frequently during the COVID-19 pandemic and declined thereafter. The reporting of platform features and the availability of results were insufficient. Premature arm closure for poor recruitment was rare.

Introducing the Library of Guidance for Health Scientists (LIGHTS): A Living Database for Methods Guidance

IMPORTANCE

Improving methodological quality is a priority in the health research community. Finding appropriate methods guidance can be challenging due to heterogeneous terminology, poor indexing in medical databases, and variation in formats. The Library of Guidance for Health Scientists (LIGHTS) is a new searchable database for methods guidance articles.

OBSERVATIONS

Journal articles that aim to provide guidance for performing (including planning, design, conduct, analysis, and interpretation), reporting, and assessing the quality of health-related research involving humans or human populations (ie, excluding basic and animal research) are eligible for LIGHTS. A team of health researchers, information specialists, and methodologists continuously identifies and manually indexes eligible guidance documents. The search strategy includes focused searches of specific journals, specialized databases, and suggestions from researchers. A current limitation is that a keyword-based search of MEDLINE (and other general databases) and manual screening of records were not feasible because of the large number of hits (n = 915 523). As of September 20, 2022, LIGHTS included 1246 articles (336 reporting guidelines, 80 quality assessment tools, and 830 other methods guidance articles). The LIGHTS website provides a user-oriented search interface including filters for study type, specific methodological topic, research context, guidance type, and development process of the guidance. Automated matching of alternative methodological expressions (eg, enter loss to follow-up and find articles indexed with missing data) enhances search queries.

CONCLUSIONS AND RELEVANCE

LIGHTS is a peer-supported initiative that is intended to increase access to and use of methods guidance relevant to health researchers, statisticians, methods consultants, methods developers, ethics boards, peer reviewers, journal editors, and funding bodies.