Health-related quality of life in the Brazilian Amazon: a population-based cross-sectional study

Background To analyze perceptions of health-related quality of life and associated factors in populations from the Manaus Metropolitan Region. Methods We conducted a population-based cross-sectional study from May to August 2015. Adults aged 18 years and older were selected using probabilistic three-phase cluster sampling and stratified by sex and age, based on official estimates. Quality of life data were collected using the European Quality of Life 5-Dimensions 3-Levels (EQ-5D-3L) along with socioeconomic, demographic, and health perception data. Utility scores were calculated using the Brazilian version of the EQ-5D-3L. Descriptive statistics were derived, and a multivariate Tobit regression model with correction for complex sampling was performed to identify the variables that influence utility levels. Results A total of 4001 participants were included. The average utility score was 0.886 (95% confidence interval [CI]: 0.881–0.890) with significant differences according to living area (the capital (0.882 ± 0.144) or inner cities (0.908 ± 0.122; p