Bias in the Analysis of Repeated-Measures Designs: Some Alternative Approaches

MCCALL, ROBERT B., and APPELBAUM, MARK I. Bias in the Analysis of Repeated-Measures Designs: Some Alternative Approaches. CHILD DEVELOPMENT, 1973, 44, 401-415. The conventional analysis of variance applied to designs in which each subject is measured repeatedly requires stringent assumptions regarding the variance-covariance (i.e., correlations among repeated measures) structure of the data. Violation of these assumptions results in too many rejections of the null hypothesis for the stated significance level. This paper considers several alternatives when heterogeneity of covariance exists, including nonparametric tests, randomization and matching procedures, Box and Greenhouse-Geisser corrections, and multivariate analysis. The presentation is from an applied rather than theoretical standpoint. Multivariate techniques that make no covariance assumptions and provide exact probability statements represent the most versatile solution.