THE FEASIBILITY, RELIABILITY AND VALIDITY OF THE EORTC QLQ-C30 IN ASSESSING THE QUALITY-OF-LIFE OF PATIENTS WITH A SYMPTOMATIC HIV-INFECTION OR AIDS (CDC-IV)

The objective of this study was to evaluate the feasibility, reliabili ty and validity of the European Organization for Research and Treatmen t of Cancer Quality of Life Questionnaire (the QLQ-C30) in a longitudi nal study of the quality of life (QoL) of patients with a symptomatic HIV infection or AIDS. The OLQ-C30 is a 30-item questionnaire composed of five functional subscales, 3 symptom subscales, an overall QoL sub scale, and a number of additional single item symptom measures. The qu estionnaire was administered serially to a sample of 156 Dutch patient s. The average time to complete the questionnaire was less than 11 min utes, with most patients requiring no assistance. With one exception ( role functioning subscale), the data supported the hypothesized scale structure of the questionnaire. Eight of the 9 subscales met or approa ched the minimal criterion for reliability (Cronbach's alpha greater-t han-or-equal-to .70) at baseline and/or follow-up. The validity of the QLQ-C30 was supported by 3 findings: (1) the correlations observed am ong the subscales, while statistically significant, were of only a mod erate magnitude, indicating that distinct components of QoL are being assessed; (2) a number of the subscales could discriminate clearly bet ween patients differing in stage of disease and in Karnofsky Performan ce Status; and (3) significant changes in QLQ-C30 scores in the expect ed direction, were observed over time. These results lend support to t he QLQ-C30 as a reasonably reliable and valid instrument for assessing the QoL of patients with HIV infection. Additional research is needed to improve the role functioning subscale, to evaluate the QLQ-C30's c oncurrent validity by comparing it with other available QoL instrument s, and to examine more thoroughly its responsiveness to clinically imp ortant changes in patients' health status over the entire disease and treatment trajectory.