Population prevalence of psychiatric disorders in Chile: 6-month and 1-month rates.

Background: Few South American studies have examined current prevalence rates of psychiatric disorders.

Aims: To examine prevalence rates in a nationally representative adult population from Chile.

Method: The Composite International Diagnostic Interview was administered to a stratified random sample of 2978 individuals from four provinces representative of the country's population. Six-month and 1-month prevalence rates were estimated. Demographic correlates, comorbidity and service use were examined.

Results: Nearly a fifth of the Chilean population had had a psychiatric disorder during the preceding 6 months. The 6-month and 1-month prevalence rates were 19.7% and 16.7% respectively. For the 6-month prevalence the five most common disorders were simple phobia, social phobia, agoraphobia, major depressive disorder and alcohol dependence. Less than 30% of those with any psychiatric diagnosis had a comorbid psychiatric disorder and the majority of them had sought treatment from mental health services.

Conclusions: Current prevalence studies are useful indicators of service needs. People with comorbid psychiatric conditions have high rates of service use. The low rate of comorbidity in Chile merits further study.