Mixed Models for Longitudinal Data Analysis
Friday, May 22, 2009,
9:00 AM - 12:50 PM
Yerba Buena 1 - 2
In this workshop, attendees will learn about the use of mixed models for analysis of longitudinal, or repeated measures, data. The focus will be on application of these models, with direct application illustrated using standard statistical software (i.e., SPSS). The basic mixed model will be introduced and described, including use of polynomials for expressing change across time, the multilevel representation of the model, treatment of time-invariant and time-varying covariates, and modeling of the variance-covariance structure of the repeated measures. Some aspects of model estimation and inference will be covered. Methods will be illustrated using a psychiatric study in which patients’ depression levels are modeled over time. Several examples using SPSS MIXED will be performed and described, including how to set up the data for the analyses, what options are available for the analyses, how to run the analyses, and how to interpret the output.