K-sample test and sample size calculation for comparing slopes in data with repeated measurements

Journal Article (Journal Article)

Sample size calculations based on two-sample comparisons of slopes in repeated measurements have been reported by many investigators. In contrast, the literature has paid relatively little attention to the design and analysis of K-sample trials in repeated measurements studies where K is 3 or greater. Jung and Ahn (2003) derived a closed sample size formula for two-sample comparisons of slopes by taking into account the impact of missing data. We extend their method to compare K-sample slopes in repeated measurement studies using the generalized estimating equation (GEE) approach based on independent working correlation structure. We investigate the performance of the sample size formula since the sample size formula is based on asymptotic theory. The proposed sample size formula is illustrated using a clinical trial example.

Full Text

Duke Authors

Cited Authors

  • Jung, SH; Ahn, C

Published Date

  • September 1, 2004

Published In

Volume / Issue

  • 46 / 5

Start / End Page

  • 554 - 564

International Standard Serial Number (ISSN)

  • 0323-3847

Digital Object Identifier (DOI)

  • 10.1002/bimj.200310050

Citation Source

  • Scopus