Quality of Life: Design and Analyses Issues in Clinical Trials

Abstract

The assessment of quality of life (QOL) has become an integral part of drug development process in pharmaceutical industries. The QOL measures are frequently used as both primary and secondary endpoints in clinical trials. The QOL is becoming of greater importance in differentiating drugs for which traditional measures of efficacy and safety are similar. Apart from assessing the treatment effects on QOL measures, we also need to examine its association with the plasma drug concentrations. In this paper, we address some of the important statistical design and analysis issues using a cancer clinical trial. In particular, we address the sample size and power estimation issues using a model that describes the association between the QOL measures and the plasma concentrations. We also present a statistical methodology to assess treatment differences in QOL data that are collected as multivariate repeated measures.

Key Words:

• QOL
• Validation
• Repeated measure

Mathematics Subject Classification:

• 62Pxx
• 62P10

Acknowledgment

We thank the two reviewers for suggestions that improved the presentation of this manuscript.