[Epidemiology of mental disorders in Spain: methods and participation in the ESEMeD-Spain project]

The ESEMeD-Spain study is part of a European project on the epidemiology of mental disorders, which is also part of a World Health Organization initiative called World Mental Health Surveys. The main objectives of the study are to estimate the prevalence of mental disorders in Spain; to analyze their association with sociodemographic variables and predisposing and protective factors; to evaluate their impact on the quality of life; and to describe and evaluate the health care received by people with mental disorders.

A representative sample of the noninstitutionalized Spanish population older than 18 years is interviewed. Sample size is 5,500 people. The instrument used in the interviews is the Composite International Diagnostic Interview (CIDI), a questionnaire designed to be used by lay interviewers that allows the diagnosis of psychiatric disorders. Strict quality control of field work has been established. Furthermore, approximately 200 subjects are re-interviewed by a psychiatrist using the Structured Clinical Interview for DSM-IV (SCID) and several questionnaires to measure clinical severity.

Field work started in September 2001 and finished in November 2002. Up to Ap ril 2002, more than 4,300 people have been interviewed. Preliminary response rate has been 68.7%. Comparison of the age and gender of the study sample with the general Spanish population shows high representativeness.

The ESEMeD-Spain project will produce un - precedented scientific information about the epidemiology of mental disorders in Spain.