An example of using mixed models and PROC MIXED for longitudinal data.

R D Wolfinger

doi:10.1080/10543409708835203

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An example of using mixed models and PROC MIXED for longitudinal data.

R D Wolfinger

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Abstract

Longitudinal data, or data that are repeated measurements on various subjects across time, are commonplace in biostatistical studies. The general linear mixed model is a useful statistical tool for analyzing such data and drawing meaningful inferences about them. This paper discusses some of the most common mixed models and fits them to a prototypical example involving repeated measures on blood pressure. Computer implementation is via the MIXED procedure in the SAS System, and code descriptions and output interpretations accompany the example.

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R D Wolfinger. 1997. An example of using mixed models and PROC MIXED for longitudinal data.. https://doi.org/10.1080/10543409708835203

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