Psychiatric cases identification by multi steps epidemiological studies: methods, problems and applicability

Abstract

OBJECTIVE: To discuss methodological aspects of the two stages in the identification of psychiatric cases in epidemiological studies. METHODS: Analyze the methodology used in the Multicentric Psychiatric Morbidity Study, which was conducted in three Brazilian cities (São Paulo, Brasília and Porto Alegre). In the first stage of that study, a random sample (6,740 individuals) of the population was drawn and all the participants were screened with the Questionnaire of Psychiatric Morbidity of the Adult (QMPA). In the second stage, a sample (775 individuals) of this population was drawn and these individuals were submitted to the Inventory of Symptoms of DSM-III, carried out by psychiatrists and trained psychologists. RESULTS: The study procedure for estimating the prevalence is described in details, showing that though the screening scales are a weak tool, they don't interfere with the methodology. CONCLUSION: The advantage of this methodology is to correct any distortions caused by the current tools used in the identification of psychiatric cases.