The aim of this thesis was to enhance the validity of clinical diagnostics of alcoholism. More specifically the aim was to provide the clinician with a method to confirm the diagnosis of alcoholism. This method was eventually used in populations of drivers under influence (DUI's). First the discriminant validity of Alcohol Use Disorder (AUD) diagnoses according to DSM-IV was studied within a population of well-functioning male heavy drinkers (chapter two). This study was conducted in order to explore whether it is possible to infer Alcohol Use Disorders from biochemical tests, clinical signs and clinical symptoms indicative of hazardous alcohol use. No significant differences were found between individuals with AUD and those without AUD. In two different studies among DUI's, different methods were used to obtain a prevalence-estimate of alcoholism in a DUI-population. It was found that the prevalence of alcoholism in the DUI population is around 50% (chapter three and six). It was also found that interviews like SCID and CIDI are inadequate instruments to diagnose alcoholism in DUI's as they result in serious under-diagnosis. In the study described in chapter four the diagnostic accuracy of two tests for hazardous alcohol use (HAU) were compared : one %CDT-test including asialo-, monosialo-, disialo- and trisialo-isoforms and one without the trisialo-isoforms, and found that the CDT test without trisialo-isoforms had greater diagnostic accuracy. The most important aim of this dissertation was the development of a confirmation test for diagnosing HAU. In chapter five, the development of a confirmation test, the Bayesian Alcoholism Test (BAT), is described. Furthermore, BAT is validated and compared to single diagnostic tests in populations of treatment-seeking alcoholics, non-treatment-seeking heavy drinkers and non-alcoholic controls. It was found that BAT has better diagnostic properties than CDT and GGT for confirming HAU. Since the primary goal was to develop a confirmation diagnostic test in the context of medical examination of DUI's, BAT was compared to conventional methods used for diagnosing alcoholism in DUI's (chapter six). Because a gold standard for alcoholism does as yet not exist, alternative standards were used to validate BAT. The results of BAT and a Clinical Diagnostic Procedure (CDP) are most closely related to prevalences found in standard clinical practice. The advantage of BAT above CDP is that it is more objective because each subject is diagnosed in the same - objective - way. (Author/publisher)
Samenvatting