BACKGROUND: We evaluated the natural history of psychopathology in a stratified sample (n = 245) comprising subjects with no DSM-III-R psychiatric disorder, subthreshold disorder and threshold (DSM-III-R) psychiatric disorder, respectively, over a 12-months period, using the Structured Clinical Interview for DSM-III-R mental disorders (SCID) as an assessment tool. METHODS: A representative sample categorized 1 year earlier into DSM-III-R psychiatric disorder, subthreshold disorder and no DSM-III-R psychiatric disorder were reassessed with SCID 1 year on. The incidence, recovery rates and the percentage of subthreshold disorders which become DSM-III-R disorders were calculated. The utilization rate of psychiatric services was also assessed. RESULTS: The incidence rate of new cases was 10.4%. The recovery (remission) rate was 41.5%, and approximately 20% of subthreshold disorders became definitive disorders (DSM-III-R) after 1 year. Anxiety disorders tend to have a higher magnitude of temporal stability in comparison with depressive disorders. Male sex and contact with psychiatric services were found to affect the recovery rate. Approximately 13% of the sample had made contact with psychiatric services with no gender differences, but men were significantly more often hospitalized than women. CONCLUSION: Our findings indicate that mental disorders are relatively common. The high incidence rate found in this study is attributed in part to the high negative rate at baseline assessment. Approximately 60% of psychiatric disorders in the community are persistent, and patients with emotional disorder under-utilize existing services.