Soc Psychiatry Psychiatr Epidemiol (1994) 29:83-87 9 Springer-Verlag 1994 L. Hansson 9 R Nettelbladt 9 L. Borgquist 9 G. NordstrOm Screening for psychiatric illness in primary care A cross-sectional study in a Swedish health district Accepted: 2 November 1993 Abstract A sample of 388 primary care patients in a Swedish health district were screened for psychiatric ill- ness using the Hopkins Symptom Check List HSCL-25. General practitioner (GP) ratings of psychiatric illness and patient ratings of psychosocial problems were also in- cluded. Data concerning the patients' utilization of care and health insurance were recorded. According to the HSCL-25, 30.2 % of the patients were probable psychiat- ric cases and 19.2% were psychiatric cases in need of treatment. According to GPs' independent ratings, 12.3 % of the patients suffered from psychiatric illness re- quiring treatment. Psychiatric cases according to HSCL- 25 were more often women, divorced, unemployed and living alone. During the year preceding index contact, psychiatric cases showed a higher utilization of primary care, as well as other somatic care. They also had more sick leave. Psychiatric cases perceived higher levels of psy- chosocial problems in areas of unemployment, work situ- ation, private economy, child care and social isolation. The results of the study point to the interaction of psycho- logical impairment, environmental stress and lack of so- cial support in producing psychiatric illness. Introduction There are considerable differences in rates of prevalance in estimates of psychiatric illness in primary care settings. These differences may be related to differences in psy- chiatric morbidity in the populations studied, but may also be due to differences in the instruments used to rate psy- chiatric illness and in criteria used to define psychiatric caseness. Differences in the care organizations studied L.Hansson (~). ENenelbladt- G.NordstrOm Department of Psychiatry, University Hospital, S-221 85 Lurid, Sweden L. Borgquist Department of Community Health Services, Lund University, Dalby, Sweden may also account for part of the variance [1]. The use of standardized questionnaires in screening for psychiatric illness have generally shown prevalence rates in the range 16--43 % [2-4]. Patients screened or diagnosed as psychiatric cases in primary care have been shown to be more often women, not married, unemployed and older [3, 5, 6]. The rate of detection of psychiatric illness, the conspicuous psychi- atric morbidity [7], has also been related to characteristics of the general practitioner (GP), situational factors and to matching factors between the GP and the patient [8, 9]. Two-stage studies using comparisons between GP ratings and a screening test and/or a standardized psychi- atric interview have revealed various rates of hidden psy- chiatric morbidity in primary care [4, 8, 10]. In the Nordic countries, studies using two-stage designs in screening for psychiatric illness in primary care are lacking. The present study is part of a Nordic comparative multicentre study in- vestigating psychiatric morbidity in primary care and pathways to psychiatric care. In this paper, results from one of the participating Swedish health districts will be presented. The specific aims of this part of the study were to investigate the fre- quency of psychiatric illness according to a screening test and according to GP ratings, and to analyse characteristics of patients with psychiatric illness with regard to socio- demographic characteristics, utilization of care and psy- chosocial and environmental worries/problems. Methods and patients Method The study was performed in a Swedish health district as part of a Nor- dic comparative study of psychiatric morbidity in primary care and pathways to psychiatric care. All patients visiting a GP in four health centres during i specificweek were approached for the investigation, except for patients making contact for maternity care or to obtain a health certificate. Patients who agreed to participate were screened for psychiatric symptoms using a self-rating scale, the Hopkins Symp- tom Check List (HSCL-25) [11].The HSCL-25 is a 25-item scale with