Back to Search
Start Over
Reflection on modern methods: when is a stepped-wedge cluster randomized trial a good study design choice?
- Source :
- International Journal of Epidemiology; Jun2020, Vol. 49 Issue 3, p1043-1052, 10p
- Publication Year :
- 2020
-
Abstract
- The stepped-wedge cluster randomized trial (SW-CRT) involves the sequential transition of clusters (such as hospitals, public health units or communities) from control to intervention conditions in a randomized order. The use of the SW-CRT is growing rapidly. Yet the SW-CRT is at greater risks of bias compared with the conventional parallel cluster randomized trial (parallel-CRT). For this reason, the CONSORT extension for SW-CRTs requires that investigators provide a clear justification for the choice of study design. In this paper, we argue that all other things being equal, the SW-CRT is at greater risk of bias due to misspecification of the secular trends at the analysis stage. This is particularly problematic for studies randomizing a small number of heterogeneous clusters. We outline the potential conditions under which an SW-CRT might be an appropriate choice. Potentially appropriate and often overlapping justifications for conducting an SW-CRT include: (i) the SW-CRT provides a means to conduct a randomized evaluation which otherwise would not be possible; (ii) the SW-CRT facilitates cluster recruitment as it enhances the acceptability of a randomized evaluation either to cluster gatekeepers or other stakeholders; (iii) the SW-CRT is the only feasible design due to pragmatic and logistical constraints (for example the roll-out of a scare resource); and (iv) the SW-CRT has increased statistical power over other study designs (which will include situations with a limited number of clusters). As the number of arguments in favour of an SW-CRT increases, the likelihood that the benefits of using the SW-CRT, as opposed to a parallel-CRT, outweigh its risks also increases. We argue that the mere popularity and novelty of the SW-CRT should not be a factor in its adoption. In situations when a conventional parallel-CRT is feasible, it is likely to be the preferred design. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 03005771
- Volume :
- 49
- Issue :
- 3
- Database :
- Complementary Index
- Journal :
- International Journal of Epidemiology
- Publication Type :
- Academic Journal
- Accession number :
- 144891988
- Full Text :
- https://doi.org/10.1093/ije/dyaa077