Measurement of quality of life in patients: psychometric analyses of the Functional Living Index-Cancer (FLIC).

Biomedical advances in medical care and treatment have highlighted potential trade-offs between the length and quality of a patient's life. There is increasing need for psychometrically sound measurement of quality of life in medical patients. Psychometric analyses of the Functional Living Index-Cancer (FLIC) were conducted on data from 530 consecutive patients with histologically confirmed cancer. To examine construct validity, a principal components analysis was conducted that revealed a five-factor solution accounting for 70% of the variance in a random half of the original sample and 68% in a cross-replication sample. Content analysis indicated that domains of physical, psychological and social functioning are assessed along with the patient's view of their current well-being and disease symptoms. Convergent-discriminant validity was shown with independent measures of symptoms and anxiety. Most, but not all expected differences in quality of life by demographic and psychological variables were found. Within the limitations imposed by the study and its sample, the FLIC appears to be a conceptually sound, internally consistent instrument worthy of use and further study in other health care samples.