The stepped wedge cluster randomised trial: what it is and when it should be used

Campbell, Michael J; Hemming, Karla; Taljaard, Monica

doi:10.5694/mja2.50018

Topics

Statistics, epidemiology and research design

The basic premise of a stepped wedge cluster randomised trial (SW‐CRT) is that all clusters start in the control condition, and they switch to the intervention condition in an order determined by randomisation. SW‐CRTs differ from cluster crossover trials in that the switch is only in one direction, from control to intervention condition.

1 School of Health and Related Research, University of Sheffield, Sheffield, UK
2 Institute of Applied Health Research, University of Birmingham, Birmingham, UK
3 Ottawa Hospital Research Institute, Ottawa, Canada

Correspondence: m.j.campbell@sheffield.ac.uk

Series editors

John R Attia

Michael P Jones

Competing interests:

No relevant disclosures.

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