Linear Mixed Models in Clinical Trials using PROC MIXED
نویسندگان
چکیده
This paper mainly illustrates how to use PROC MIXED to fit linear mixed models in clinical trials. We first introduce the statistical background of linear mixed models. We explore the situations under which the mixed effects are identified. A randomized complete block design is used to explain the difference between PROC GLM and PROC MIXED in dealing with the linear mixed models. Examples include applications of PROC MIXED in four commonly seen clinical trials utilizing splitplot designs, cross-over designs, repeated measures analysis and multilevel hierarchical models.
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