RESUMEN
The purpose of this study is to validate the Brazilian version of Functional Assessment of Cancer Therapy-Prostate FACT-P (version 4) in nonmetastatic prostate cancer (PC) patients. Patients with histopathological diagnosis of PC were submitted to health-related quality of life (HRQOL) questionnaires - SF-36 (Medical Outcomes Study 36 - Item Short-Form Health Survey) and FACT-P (version 4). After 7 to 15 days, FACT-P (version 4) was reapplied in the sample's percentage that participated the first evaluation. Cronbach alpha coefficient was used to determine internal consistency and intraclass correlation coefficient (ICC) certified stability. Correlations between FACT-P (version 4) and SF-36 tested convergent validity. Regarding known groups validity, the hypothesis tested was that FACT-P (version 4) is capable of discriminating HRQOL in patients with different PC risk classifications. A total of 112 patients with nonmetastatic PC were evaluated. Cronbach alpha coefficients (0.64-0.88) and ICC (0.75-0.93) obtained satisfactory results of reliability. Verified correlations (r 0.3-0.72) between FACT-P (version 4) and SF-36 suggest convergent validity. In the studied sample, FACT-P (version 4) was unable to discriminate HRQOL in nonmetastatic patients. The Brazilian version of FACT-P questionnaire (version 4) showed evidences of reliability and validity on evaluating HRQOL in Brazilian men with nonmetastatic PC.