Health-related quality of life in Brazil: normative data for the SF-36 in a general population sample in the south of the country

The objective of this study was to provide normative SF-36 scores in a general population sample in Brazil and to describe differences in mean scores according to socio-demographic characteristics. The SF-36 questionnaire was distributed to a randomly selected sample of the general population of Porto Alegre in the State of Rio Grande do Sul. The response rate was 68% and 755 subjects were included (38% male, 62% female). Lower health status was revealed among females in the 30 to 44 year age bracket, from the lower income class, with less education and self-reported chronic medical conditions. The results and percentiles of scores of the SF-36 are reported as normative data for the general population. The SF-36 was an acceptable and practical instrument for measuring health-related quality of life in a sample of Brazilians. The results of this study can be useful for researchers using the SF-36 questionnaire in other groups to compare the scores with normative data. The SF-36 may prove a valuable tool for discovering vulnerable groups in epidemiological studies due to the ability to discriminate between different population subgroups.