Psychiatric case identification in two Athenian communities: estimation of the probable prevalence

A two stage cross sectional survey on the prevalence of psychiatric disorders was conducted in a sample of 1,574 adults, residents of two boroughs in the greater Athens area. In this paper we examine the value of the first stage self report symptom screening scales (CES-D and Langner) for case finding, by comparing it to five psychiatric case identification criteria, proven to be highly reliable, after the completion of an inter-rater reliability study. A higher proportion of mentally impaired respondents was found with the criterion of screening scale cut off scores than the cases found by the application of the five case identification criteria. The practical significance of establishing case finding reliable criteria is apparent for the purpose of epidemiologic research e.g. the problem of false positive and negative cases, the completion of the second stage of diagnostic interviews and for the planning of outreach programs, identifying and helping high risk individuals.