[Referring a patient: who, how, when and why? Psychiatry in relation to primary health care].
After a theoretical review of liaison psychiatry, a descriptive and comparative study of all referrals from two general practitioner's surgeries to a hospital outpatient clinic is performed. A model of liaison psychiatry in general practice is studied and its impact is comparatively assessed according to some socio-demographic and clinical variables. A sample of 81 referrals to a hospital outpatient clinic by general practitioners was examined. Some differences between the two populations (with statistical significance) are presented: the age and sex influence in the referral process, duration of symptoms, presented problems, suggestion of referral, time between first contact (first healer) and the outpatient referral and between the GP consultation and referral, previous treatment and number of total psychiatric outpatient referrals. The results, their implications and consequences, are considered and discussed for the development of an effective liaison between primary and secondary care.