title: Current issues in the design and analysis of stepped wedge trials.
abstract: The use of stepped wedge designs in cluster-randomized trials and implementation studies has increased rapidly in recent years but there remains considerable debate regarding the merits of the design. We discuss three key issues in the design and analysis of stepped wedge trials - time-on-treatment effects, treatment effect heterogeneity and cohort studies.
authors.affiliation: Department of Biostatistics, University of Washington, Seattle, WA, United States; Fred Hutchinson Cancer Research Center, Seattle, WA, United States. Electronic address: jphughes@u.washington.edu.
authors.forename: James P
authors.initials: JP
authors.lastname: Hughes
authors.affiliation: Department of Biostatistics, University of Washington, Seattle, WA, United States.
authors.forename: Tanya S
authors.initials: TS
authors.lastname: Granston
authors.affiliation: Department of Biostatistics, University of Washington, Seattle, WA, United States.
authors.forename: Patrick J
authors.initials: PJ
authors.lastname: Heagerty
mesh_terms: D015331:Cohort Studies; D003430:Cross-Sectional Studies; D006801:Humans; D016032:Randomized Controlled Trials as Topic / Q000379:methods*; D012107:Research Design; D013997:Time Factors
keywords: Cluster randomized trial; Implementation research; Stepped wedge design