Sample size calculation for cluster randomized cross-over trials

Stat Med. 2008 Nov 29;27(27):5578-85. doi: 10.1002/sim.3383.


The cluster randomized cross-over design has been proposed in particular because it prevents an imbalance that may bring into question the internal validity of parallel group cluster trials. We derived a sample size formula for continuous outcomes that takes into account both the intraclass correlation coefficient (representing the clustering effect) and the interperiod correlation (induced by the cross-over design).

MeSH terms

  • Algorithms
  • Blood Glucose / analysis*
  • Cluster Analysis*
  • Cross-Over Studies
  • Data Interpretation, Statistical
  • Drug Therapy, Computer-Assisted*
  • Humans
  • Hypoglycemic Agents / administration & dosage*
  • Insulin / administration & dosage*
  • Intensive Care Units
  • Models, Statistical*
  • Randomized Controlled Trials as Topic*
  • Research Design*
  • Sample Size*
  • Time Factors


  • Blood Glucose
  • Hypoglycemic Agents
  • Insulin