Spouse ratings of quality of life in patients with metastatic prostate cancer of lower socioeconomic status: An assessment of feasibility, reliability, and validity

Objectives. To examine the reliability and validity of spousal assessments by evaluating the collateral quality-of-life (QOL) ratings of patients of l ower socioeconomic status with metastatic prostate cancer because collatera l ratings provide supplemental information when advanced cancer limits pati ent self-report. Methods. Patients with Stage D2 prostate cancer (n = 36) of lower socioecon omic status completed validated QOL instruments (Functional Assessment of C ancer Therapy-General [FACT-G], European Organization for Research and Trea tment of Cancer-Quality of Life-30, and Quality of Life Index). Spouses com pleted a modified FACT-G, and physicians rated performance status using Kar nofsky's scale. Results. The internal consistency reliability was moderate to high for pati ent ratings on all FACT-G subscales and for spousal ratings on the modified FACT-G physical, functional, and emotional subscales. The spouses' ratings of the patients on the social and doctor relationship subscales were below the accepted criterion for a measure's use in group comparisons. The compa risons of the mean values of the FACT-G revealed agreement between patients and spouses, except that the spouses rated the patients as having poorer e motional function than did the patients. The intraclass correlations were m oderate to high for the functional and emotional subscales and were low, bu t significant, for the physical and social subscales. The patient and spous e FACT-G ratings correlated with the patient ratings and physician ratings across the instruments for the functional and physical domains (r = 0.48 to 0.77, for patients; r = 0.31 to 0.70, for spouses), with less consistent r elationships for the social and emotional domains. Conclusions. The collateral QOL assessments from spouses are potentially us eful in assessing the functional status in patients of lower socioeconomic status with metastatic prostate cancer. For subjective domains, such as the social domain, direct patient assessments are needed. UROLOGY 57: 275-280, 2001. (C) 2001, Elsevier Science Inc.