HEALTH-RELATED QUALITY-OF-LIFE IN THE GENERAL NORWEGIAN POPULATION ASSESSED BY THE -ORGANIZATION-FOR-RESEARCH-AND-TREATMENT-OF-CANCER CORE QUALITY-OF-LIFE QUESTIONNAIRE - THE QLQ=C30 (+3)

Purpose: To obtain reference data on health-related quality of life (H RQOL) for the functional and symptom scales and single items of the Eu ropean Organization for Research and Treatment of Cancer Core Quality- of-Life Questionnaire (EORTC QLQ-C30 [+ 3]) in a representative sample of the Norwegian general population. Patients and Methods: A randomly selected sample of 3,000 people from the Norwegian population, aged 1 8 to 93 years, who represent geographic diversity, took part in this p ostal survey The EORTC QLQ-C30 (+ 3) and a questionnaire about demogra phic data and health were sent by mail. A new questionnaire package wa s sent as a reminder after 3 weeks. Results: The survey yielded a high response rate with 1,965 of 2,892 eligible persons responding (68%). There was a low amount of missing data (1.8%). Internal consistency wa s highly satisfactory and yielded Cronbach's alpha coefficients greate r than 0.70 for all bur two functional scales and one symptom scale. T he sensitivity of the questionnaire was shown by the excellent discrim ination between age and sex groups. Clinical validity was shown by the distinct differences according to age and sociodemographic characteri stics. Women reported lower functional status and global quality of li fe (mean scale scores from 71.7 to 91.0) than men (mean scale scores f rom 75.4 to 94.4), and also more symptoms and problems. This was remar kably consistent across age groups, as was a decline in functional sta tus with an increase in age. Conclusion: This is the first study that presented reference data from the EORTC QLQ-C30 (+ 3) in a sample from a general population and seems to provide valid measures of HRQOL wit hin different age groups, The results may serve as a guideline for cli nicians when interpreting HRQOL in their own groups of patients, and c ontributes to a better understanding of the significance of mean score s and their clinical relevance. (C) 1998 by American Society of Clinic al Oncology.