Evidence map›Paper›PMID 40241012›Full record

ArticleBMC medical research methodology2025

Power analysis for concurrent balanced or imbalanced multiple-intervention stepped wedge design: a simulation-based approach.

Yi Zhang, Meng Zheng, Xue-Zhi Liang, Qi Wang, Kun-Peng Wu, Ting-Ting Guo, Wen Chen

Abstract read
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Article in BMC medical research methodology, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
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1citing papers in PubMed
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1 · What the graph read from it

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2 · The registry

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3 · Its place in the literature

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1 citing paper in PubMed.

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4 · The record

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5 · Who and what money

Authors and funding

7 authors.

Yi ZhangDepartment of Medical Statistics, School of Public Health, Sun Yat-Sen University, Guangzhou, China.
Meng ZhengDepartment of Medical Statistics, School of Public Health, Sun Yat-Sen University, Guangzhou, China.
Xue-Zhi LiangDepartment of Medical Statistics, School of Public Health, Sun Yat-Sen University, Guangzhou, China.
Qi WangDepartment of Medical Statistics, School of Public Health, Sun Yat-Sen University, Guangzhou, China.
Kun-Peng WuDepartment of Medical Statistics, School of Public Health, Sun Yat-Sen University, Guangzhou, China.
Ting-Ting GuoDepartment of Medical Statistics, School of Public Health, Sun Yat-Sen University, Guangzhou, China.
Wen ChenDepartment of Medical Statistics, School of Public Health, Sun Yat-Sen University, Guangzhou, China. chenw43@mail.sysu.edu.cn.

Funding

China Medical Board 20-389National Natural Science Foundation of China 82473731Science Fund for Distinguished Young Scholars of Guangdong Province 2022B1515020094
6 · The paper itself

Abstract

backgroundThe concurrent multiple-intervention stepped wedge design (M-SWD) is one of the most widely used variants of the SWD. We aimed to conduct power analysis for concurrent balanced (equal number of clusters in intervention groups) and imbalanced (unequal number of clusters in intervention groups) M-SWDs.

methodsWe conducted power analysis using a simulation-based approach with cross-sectional or closed-cohort designs and examined impact of design parameters (cluster size and number of clusters) and correlation parameters (total random effects variance (TRE), cluster autocorrelation coefficient (CAC), and individual autocorrelation coefficient (IAC)) on the powers of statistical tests for treatment effects.

resultsWith a fixed total sample size, increasing the number of clusters improves statistical power. When two treatment effects differ greatly, the concurrent imbalanced M-SWD saves sample size compared to the balanced design and powers could achieve the target value when the ratio of clusters approximates the inverse ratio of two effects. However, the allocation ratio should be no greater than 4:1. Additionally, statistical powers increased with decreasing TRE and increasing CAC and IAC. The impact of autocorrelation coefficients on powers is more pronounced when these parameters are large.

conclusionWhen two treatment effects differ greatly, the concurrent imbalanced M-SWD, with an allocation ratio no larger than 4:1, is a preferred design over the balanced one. For both concurrent balanced and imbalanced M-SWD, it is recommended to set large number of clusters with small cluster sizes and to carefully consider estimates of correlation parameters when designing the trial.

Indexed as

Computer SimulationRandomized Controlled Trials as TopicResearch DesignCluster AnalysisCross-Sectional StudiesHumansModels, StatisticalSample SizePower analysisSimulation-based approachStepped wedge designTrials

Identifiers

PMID40241012
PMCPMC12001562

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.