Sample size calculations for randomised trials including both independent and paired data
Lisa N Yelland, Thomas R Sullivan, David J Price, Katherine J Lee
STATISTICS IN MEDICINE | WILEY | Published : 2017
Randomised trials including a mixture of independent and paired data arise in many areas of health research, yet methods for determining the sample size for such trials are lacking. We derive design effects algebraically assuming clustering because of paired data will be taken into account in the analysis using generalised estimating equations with either an independence or exchangeable working correlation structure. Continuous and binary outcomes are considered, along with three different methods of randomisation: cluster randomisation, individual randomisation and randomisation to opposite treatment groups. The design effect is shown to depend on the intracluster correlation coefficient, p..View full abstract
Awarded by Australian National Health and Medical Research Council Fellowships
Lisa Yelland and Katherine Lee were supported by Australian National Health and Medical Research Council Fellowships [Early Career Fellowship ID 1052388 for L. Y., Career Development Fellowship ID 1053609 for K. L.]. This research was supported by a Women's and Children's Hospital Foundation Research Project Grant. We are grateful to an Associate Editor and two anonymous reviewers for providing helpful comments.