A three-level mixed-effects location scale model with an application to ecological momentary assessment data.

ABSTRACT: In studies using ecological momentary assessment (EMA), or other intensive longitudinal data collection methods, interest frequently centers on changes in the variances, both within-subjects and between-subjects. For this, Hedeker et al. (Biometrics 2008; 64: 627-634) developed an extended two-level mixed-effects model that treats observations as being nested within subjects and allows covariates to influence both the within-subjects and between-subjects variance, beyond their influence on means. However, in EMA studies, subjects often provide many responses within and across days. To account for the possible systematic day-to-day variation, we developed a more flexible three-level mixed-effects location scale model that treats observations within days within subjects, and allows covariate

SUBMITTER: Li X 

PROVIDER: S-EPMC3665350 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature