The 15-D Measure of Health Related Quality of Life: Reliability, Validity and Sensitivity of its Health State Descriptive System

The 15D is a generic, 15-dimensional, standardised, self-administered measure of HRQOL, that can be used both as a profile and as a single index score measure. This paper examines the acceptability, reliability, validity and sensitivity of two versions (15D.1 and 15D.2) of its health state descriptive system as a profile measure compared with the Nottingham Health Profile (NHP), SF20 and EuroQol by using several data sets and methods. The response and completion rates show that the acceptability is comparable to NHP, SF-20 and EuroQol. Reliability in terms of repeatability is high, even higher than for NHP. There is substantial evidence of content and construct validity (cross-sectional and longitudinal) and depression-related criterion validity. On roughly comparable dimensions the discriminatory power of 15D.1 appears to be superior to NHP, at least equivalent to SF-20, that of 15D.2 superior to EuroQol and 15D.1, and the responsiveness of 15D.1 to change seems to be similar to NHP and SF-20. The remaining 9-10 dimensions of 15D provide a large extra reserve in these respects. It is concluded that as a profile measure 15D performs equally well as NHP and SF-20, in some respects even better. The properties as a single index score measure will be explored separately. The 15D-Measure of Health-Related Quality of Life: Reliability, Validity and Sensitivity of its Health State Descriptive System