Power considerations for generalized estimating equations analyses of four‐level cluster randomized trials

  title={Power considerations for generalized estimating equations analyses of four‐level cluster randomized trials},
  author={Xueqi Wang and Elizabeth L. Turner and John S. Preisser and Fan Li},
  journal={Biometrical Journal},
  pages={663 - 680}
In this article, we develop methods for sample size and power calculations in four‐level intervention studies when intervention assignment is carried out at any level, with a particular focus on cluster randomized trials (CRTs). CRTs involving four levels are becoming popular in healthcare research, where the effects are measured, for example, from evaluations (level 1) within participants (level 2) in divisions (level 3) that are nested in clusters (level 4). In such multilevel CRTs, we… 

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