Longitudinal beta regression models for analyzing health-related quality of life scores over time.

ABSTRACT:

Background

Health-related quality of life (HRQL) has become an increasingly important outcome parameter in clinical trials and epidemiological research. HRQL scores are typically bounded at both ends of the scale and often highly skewed. Several regression techniques have been proposed to model such data in cross-sectional studies, however, methods applicable in longitudinal research are less well researched. This study examined the use of beta regression models for analyzing longitudinal HRQL data using two empirical examples with distributional features typically encountered in practice.

Methods

We used SF-6D utility data from a German older age cohort study and stroke-specific HRQL data from a randomized controlled trial. We described the conceptual differences between mi

SUBMITTER: Hunger M 

PROVIDER: S-EPMC3528618 | biostudies-literature | 2012 Sep

REPOSITORIES: biostudies-literature