Measurement of health-related quality of life in multiple myeloma

When a randomized trial (NMSG 4/90) comparing treatment with melphalan/prednisone to melphalan/prednisone + interferon alpha-2b in newly diagnosed multiple myeloma was inititated in 1990, a quality-of-life assessment was integrated into the study. We used the questionnaire (QLQ-C30) developed by the European Organization of Research and Treatment of Cancer (EORTC) Study Group on Quality of Life. The QLQ-C30 incorporates five functional scales, three symptom scales, a global health and quality-of-life scale and some single symptom measures, The questionnaire was completed prior to treatment and after 1, 6, 12, 24, 36 and 48 months. 524 (90.2%) of 581 patients enrolled in the NMSG 4/90 completed the first questionnaire, and 484 (83.3%) completed all questionnaires given to them. All but one of the scales met the minimum criteria of reliability (Cronbach's alpha greater than or equal to 0.70). Validity was shown by (1) the ability of the scales to discriminate clearly between patients differing in clinical status as defined by pretreatment W.H.O. performance index and Durie & Salmon stage, and (2) the sensitivity to changes in objective disease status (response and relapse), This is the first report of the measurement of health-related quality of life in a prospective clinical trial in multiple myeloma. The results demonstrate that the QLQ-C30 is a reliable and valid instrument for the measurement of quality of life in these patients. The data will be used for a cost-utility analysis of the results of the NMSG 4/90 trial.