Development of a quality of life index for patients with cancer.

This study developed an instrument to measure the quality of life (QOL) of patients with cancer that would account for individual values, as well as satisfaction. The sample consisted of patients with breast cancer (n = 111) listed in the tumor registry of a major hospital. Ferrans and Power's Quality of Life Index (QLI) was modified based on an extensive review of the oncology literature, which supported content validity. The findings supported the internal consistency reliability of the entire QLI (alpha = 0.95) and of the four subscales: health and functioning, socioeconomic, psychological/spiritual, and family (alphas = 0.90, 0.84, 0.93, and 0.66, respectively). Support for concurrent validity was provided by a strong correlation (r = 0.80) between the QLI and a measure of satisfaction with life. Support for construct validity was provided by significantly higher mean QOL scores for subjects who had less pain, less depression, and were coping better with stress, using the known group technique. The positive results obtained from this assessment and the fact that many patients can complete the QLI independently are important variables to consider when health professionals are selecting instruments for research and practice.