Estimating prevalence of alcohol abuse and dependence in one general hospital: An approach to reduce sample selection bias

Prevalence estimates of alcohol abuse or dependence in general hospitals ar e often limited to single wards, small data collecting periods or insuffici ent diagnostic procedures. Therefore, the present study aimed to ascertain alcohol abuse or dependence in one general hospital, to compare prevalence data for all the 11 wards and 6 intake months, to establish if screening is sufficient or if a two-step diagnostic procedure is needed, and to determi ne whether information for an alcohol diagnosis on suspicion is available. A sample of 1309 medical or surgical in-patients were screened by questionn aires or medication for withdrawal, and, if screening-positive, were interv iewed with the alcohol section of a standardized psychiatric interview. In screening-negative patients, a diagnosis on suspicion was given if medicati on to treat withdrawal had been used, or if there was evidence of single cr iteria of alcohol dependence, somatic disorders from alcohol drinking, rais ed laboratory parameters on grounds of alcohol drinking or of self-reported high alcohol consumption. Of the medical and surgical in-patients, 20.7 an d 16.0% respectively were alcohol abusers or dependants, with a range of pr evalence rates of alcohol abuse or dependence among wards of 11.1-32.9% and among intake months between 11.3 and 28.7%. Of the medical department in-p atients, 1.9%, and of the surgical in-patients, 2.1%, were screened as fals e-positive cases. In addition, 5.5% of the medical and 12.0% of the surgica l patients were given a diagnosis on suspicion. It is concluded that all ge neral wards and different intake months should be taken into account when e stimating prevalence of alcohol abuse or dependence in a general hospital.