The Karnofsky Performance Status Scale re-examined: a cross-validation with the EORTC-C30.

A cross-validation of the Karnofsky Performance Status (KPS) and quality of life (QOL) as measured by item 30 of the quality of life questionnaire developed by the European Organization for Research and Treatment of Cancer Study Group (EORTC QLQ-C30) was conducted using ordered logit analysis and prospective data from a continuous sample of 139 lung cancer patients. The QOL is found to be a much broader concept than the KPS, since it likely captures not only physical functioning but also functioning in the non-physical dimensions of social, emotional, and possibly cognitive well-being as well as the level of distress in the physical dimensions of pain, breathing and fatigue. These results suggest that the palliative treatment of advanced cancer and the terminally ill should be guided by a broad concept of well-being that goes beyond one based only on physical functioning.