Objective: To estimate the prevalence of depressive symptoms and major depressive disorder, as assessed in population-based cross-sectional studies of Brazilian adults.

Methods: We performed a systematic review of the literature. The major databases were searched up through October 2013. Two researchers selected the studies, extracted the data, and assessed their methodological quality. Meta-analyses were performed using random effects.

Results: Of the 2,971 records retrieved, we selected 27 studies that assessed the prevalence of depression morbidity in 464,734 individuals (66% women). Eleven different screening tools were used to assess depression morbidity. The prevalence of depressive symptoms was 14% (95% confidence interval [95%CI] 13-16; I2 = 99.5%), whereas the 1-year prevalence of major depressive disorder was 8% (95%CI 7-10; I2 = 86.7%), and the lifetime prevalence of major depressive disorder was 17% (95%CI 14-19; I2 = 91.6%). All rates were higher in women than in men. No causes of heterogeneity could be identified.

Conclusion: Depression morbidity was common among Brazilian adults, and affects more women than men. Inconsistencies across studies highlight the need for standardization of future research. Clinicians should routinely investigate for the presence of depression morbidity in this population.