Stepped wedge designs: insights from a design of experiments perspective.

@article{Matthews2017SteppedWD,
  title={Stepped wedge designs: insights from a design of experiments perspective.},
  author={J N S Matthews and Andrew B Forbes},
  journal={Statistics in medicine},
  year={2017},
  volume={36 24},
  pages={
          3772-3790
        }
}
Stepped wedge designs (SWDs) have received considerable attention recently, as they are potentially a useful way to assess new treatments in areas such as health services implementation. Because allocation is usually by cluster, SWDs are often viewed as a form of cluster-randomized trial. However, since the treatment within a cluster changes during the course of the study, they can also be viewed as a form of crossover design. This article explores SWDs from the perspective of crossover trials… 
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It is observed that the statistical test that uses data only relevant to a specific intervention has inferior power compared to the test when using all the study data, and power is reduced when both the total number of periods and lag are decreased simultaneously.
Analysis of stepped wedge cluster randomized trials in the presence of a time-varying treatment effect
Stepped wedge cluster randomized controlled trials are typically analyzed using models that assume the full effect of the treatment is achieved instantaneously. We provide an analytical framework for…
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References

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