In this presentation, issues that influenced the development of policies for inclusion of quality of life end points in cer-In this review, we address issues and methods associated with measurement of quality of life in clinical trials and recommend specific instruments appropriate for clinical trials research. Our review was initiated in November 1987 at the request of the Southwest Oncology Group Cancer Control Research Committee. One motivation for the assessment of quality of life was the increased attention to cancer control research, both at the National Cancer Institute and in the Southwest Oncology Group. We circulated a position paper among the leaders of the Southwest Oncology Group recommending how and to what extent quality of life end points should be included in the group's clinical trials. Our recommendations were adopted by the Cancer Control Research Committee in October 1988. The policies we developed for assessing quality of life in selected trials are potentially relevant, with appropriate modifications, to other multi-institution clinical trials.The Southwest Oncology Group was organized in 1956 with the objectives of reducing mortality from cancer and improving care of patients with malignant disease. Participating medical institutions work together to conduct cancer clinical trials that evaluate the efficacy of cancer therapies. In the last 12 months, approximately 4,000 cancer patients were registered in 130 studies; 69% were in randomized comparative phase HI trials.The benefits of a cancer treatment regimen should outweigh its cost in patient suffering (7,2). By adding quality of life end points to the traditional end points of overall survival, disease-free survival, and tumor response, medical researchers can make more informed decisions about risk-benefit trade-offs; for example, two types of survival-quality of life trade-offs can be described. In one case, two treatments are associated with similar survival rates, but one treatment produces more severe toxic effects; in another case, one of two treatments demonstrates a better survival rate but has more severe toxic effects (3). Quality of life data can add to medical knowledge obtained in the conduct of clinical trials; such data do not supplant existing traditional end points, nor do they replace data on toxic effects based on physician reports.Received October 24, 1988; revised January 3, 1989; accepted January 4, 1989. Supported by Public Health Service grant CA-37429 from the National Cancer Institute, National Institutes of Health, Department of Health and Human Services. Based in part on work completed by Dr. C. M. Moinpour while she was a National Research Service Award postdoctoral fellow Barofsky (4) argued that many clinical trials have paid at least implicit attention to quality of life issues, e.g., the focus of the National Surgical Adjuvant Breast and Bowel Project on the survival time associated with different degrees of surgery. Other trials (5-70) with breast cancer patients address quality of life issues expl...