14.Randomization04.Cluster Stepped Wedge - sporedata/researchdesigneR GitHub Wiki
- A stepped wedge trial is used when the intervention is considered safe and very likely effective, being stable over time, and potentially not requiring informed consent.
- The intervention is unlikely to be changed over time, and health system factors (external to the intervention) are unlikely to change and modify it effect over time. For example, a new hospital policy that improves quality of care is unlikely to be instituted while the trial is ongoing.
- Multiple sites interested in conducting the study
- Funding to meet all logistical requirements to a randomized trial
- Equipoise
The intervention is progressively added to each site until all sites have it, making it a patient-centered design.
The more traditional stepped wedge design is frequent, although Bayesian alternatives have been reported [1]. The main characteristic of a stepped wedge trial is that the intervention is progressively added to each site (through randomization) until all sites have it. This design leads to a series of pros and cons:
- Stepped wedge trials are interesting if researchers believe that the intervention is safe enough to be implemented at every single site at the end of the study.
- Recruitment can be faster, although informed consent can be an issue.
- It is important for the intervention to not be influenced by any temporal trends (modifications in the surrounding healthcare system occurring as the trial is deployed)
- The design is particularly helpful if there is a high degree of heterogeneity across sites, for example in multinational studies
- CONSORT adaptation to stepped wedge [2].
- The stepped wedge cluster randomized trial: rationale, design, analysis, and reporting [3].
- Guidelines for the Content of Statistical Analysis Plans in Clinical Trials [4].
- Bayesian multilevel models
- Books
- Cluster Randomised Trials - see section 8.2.4
- Articles
- The need to balance merits and limitations from different disciplines when considering the stepped wedge [5].
- The stepped-wedge clinical trial [6].
- Treatment effects in multicenter randomized clinical trials [7].
- Common references for randomized designs
[1] Cunanan KM, Carlin BP, Peterson KA. A practical Bayesian stepped wedge design for community-based cluster-randomized clinical trials: the British Columbia Telehealth Trial. Clinical Trials. 2016 Dec;13(6):641-50.
[2] Hemming K, Taljaard M, McKenzie JE, Hooper R, Copas A, Thompson JA, Dixon-Woods M, Aldcroft A, Doussau A, Grayling M, Kristunas C. Reporting of stepped wedge cluster randomised trials: extension of the CONSORT 2010 statement with explanation and elaboration. BMJ. 2018 Nov 9;363:k1614.
[3] Hemming K, Haines TP, Chilton PJ, Girling AJ, Lilford RJ. The stepped wedge cluster randomised trial: rationale, design, analysis, and reporting. Bmj. 2015 Feb 6;350:h391.
[4] Gamble C, Krishan A, Stocken D, Lewis S, Juszczak E, Doré C, Williamson PR, Altman DG, Montgomery A, Lim P, Berlin J. Guidelines for the Content of Statistical Analysis Plans in Clinical Trials](https://jamanetwork.com/journals/jama/fullarticle/2666509). Jama. 2017 Dec 19;318(23):2337-43.
[5] de Hoop E, van der Tweel I, van der Graaf R, Moons KG, van Delden JJ, Reitsma JB, Koffijberg H. The need to balance merits and limitations from different disciplines when considering the stepped wedge. BMC medical research methodology. 2015 Dec 1;15(1):93.
[6] Ellenberg SS. The stepped-wedge clinical trial. Jama. 2018 Feb 13;319(6):607-8.
[7] Senn SJ, Lewis RJ. Treatment effects in multicenter randomized clinical trials. Jama. 2019 Mar 26;321(12):1211-2.