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

Abstract

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

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

“…Pairing this knowledge with our companion review of developments in the design of GRTs, 8 we hope that our review leads to continued improvements in the design and analysis of GRTs.…”

“…While design strategies such as restricted randomization 8 can help to achieve baseline covariate balance, they may not be easy to implement (e.g. if group characteristics are unknown in advance) and chance imbalance may arise regardless.…”

“…The goal of the current paper is to focus on developments in analytic methods, including those relevant to designs described in a companion paper that focuses on developments in GRT design. 8 As a pair, these papers update the 2004 review. With both papers, we seek to provide a broad and comprehensive review to guide the reader to seek out appropriate materials for their own circumstances.…”

Reducing Cardiovascular Disparities Through Community-Engaged Implementation Research

“…88,99 For example, use of the steppedwedge design, in which all communities or sites receive the intervention in a phased approach, can be a helpful strategy to maintain community engagement when the alternative of potential randomization to a nonintervention comparison group is viewed unfavorably. [100][101][102] Researchers may use low-burden measures to assess the quality, quantity, speed, and extent of implementation 103 in the real-world systems and find ways that are practical, feasible, and align with the needs and mission of the service provider or community. Unobtrusive measures, 104 which involve data sources already being collected during service delivery, can be invaluable.…”

Phase III Clinical trials: what methodology?

“…Randomized clinical trials serve as the standard for clinical research and have contributed immensely to advances in patient care. Nevertheless, several shortcomings of randomized clinical trials have been noted, including the need for a large sample size and long study duration, the lack of power to evaluate efficacy overall or in important subgroup [3].…”