Assessing quality of life in men with clinically localized prostate cancer: Development of a new instrument for use in multiple settings

Background: Quality of life in prostate cancer patients with clinically loc alized disease has become the focus of increasing attention over the past d ecade. However, few instruments have been developed and validated to assess quality of life specifically in this patient population. Objective: The pu rpose of this investigation was to create a comprehensive, multi-scale qual ity of life instrument that can be tailored to the needs of the clinician/i nvestigator in multiple settings. Design, subjects, and measures: Patients diagnosed with clinically localized prostate cancer were mailed a questionn aire consisting of new and previously validated quality of life items and a ncillary scales. Data from returned questionnaires were analyzed and used t o create a multi-scale instrument that assesses the effects of treatment an d disease on urinary, sexual, and bowel domains, supplemented by a scale as sessing anxiety over disease course/effectiveness of treatment. The instrum ent was then mailed to a second sample of prostate cancer patients once and then again two weeks later to assess test-retest reliability. To assess fe asibility in clinical settings, the instrument was self-administered to a t hird patient sample during a urology clinic visit. Results: All scales exhi bited good internal consistency and test-retest reliability, convergent and discriminant validity, and significant correlations with disease specific, generic health-related, and global measures of quality of life. Men with g reater physiologic impairment reported more limitations in role activities and more bother. Scales were also able to differentiate patients undergoing different therapies. All scales exhibited negligible correlations with a m easure of socially desirable responding. Additionally, the instrument prove d feasible when used as a self-administered questionnaire in a clinical set ting. Conclusions: The current instrument possesses brief multi-item scales that can be successfully self-administered in multiple settings. The instr ument is flexible, relatively quick, psychometrically reliable and valid, a nd permits a more comprehensive assessment of patients' quality of life.