Limitations of ordinary least squares models in analyzing repeated measures data.

  title={Limitations of ordinary least squares models in analyzing repeated measures data.},
  author={Carlos Ugrinowitsch and Gilbert W. Fellingham and Mark D. Ricard},
  journal={Medicine and science in sports and exercise},
  volume={36 12},
PURPOSE To a) introduce and present the advantages of linear mixed models using generalized least squares (GLS) when analyzing repeated measures data; and b) show how model misspecification and an inappropriate analysis using repeated measures ANOVA with ordinary least squares (OLS) methodology can negatively impact the probability of occurrence of Type I error. METHODS The effects of three strength-training groups were simulated. Strength gains had two slope conditions: null (no gain), and… 

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