New methods in psychiatric epidemiology

Research on the epidemiology of mental disorders has now reached the stage where it is possible for comparisons to be cautiously made between populati on samples. This is made possible for thr following reasons: recognition th at the populations at risk, including their age composition and exclusions, must be clearly specified; the use of the standardized diagnostic criteria in international use (ICD-10 and DSM-IV); and standardized clinical assess ments, such as the Schedule for Clinical Assessment in Neuropsychiatry, the Diagnostic Interview Schedule (DIS) or Composite International Diagnostic Interview (CIDI), including the automated CIDI-A, and for the elderly, the Geriatric Mental State Examination and the Canberra Interview for the Elder ly. Some recommendations are made for future epidemiological studies, inclu ding these advances in methodology Emphasis is given to the value of using continuous measures of symptoms, in addition to categorical diagnoses. In r esearch on etiology, investigators should make every effort to test innovat ive hypotheses, particularly where these involve both biological and psycho social variables.