Diagnosing alcoholism in high-risk drinking drivers: Comparing different diagnostic procedures with estimated prevalence of hazardous alcohol use

In several European countries, drivers under influence (DUI), suspected of an alcohol use disorder (AUD, 'alcoholism') are referred for diagnostic exa mination. The accuracy of diagnostic procedures used in diagnosing AUD in t he DUI population is unknown. The aim of this study was to compare three pr evalence estimates of AUD based on a structured clinical interview (SCID), a restrictive diagnostic procedure (RDP) and usual clinical diagnostic proc edure (CDP), with a prevalence estimate based on sensitivity and specificit y data of biological markers of excessive use of alcohol in non-judicial sa mples. The latter unbiased estimate provides an external yardstick against which the biased patient-based prevalence estimates in this special sample can be evaluated. The unbiased estimate derived from sensitivity and specif icity data resulted in a prevalence estimate of excessive use of alcohol be tween 74 and 82%, which is much higher than the three diagnostic procedures . SCID identified maximally 5% of alcoholics found with the unbiased estima te. RDP identified greater than or equal to 31% of the unbiased estimate, w hile CDP identified greater than or equal to 60% of the unbiased estimate. The high chance of false positive diagnosis, however, makes CDP unacceptabl e in the legal context of AUD diagnosis in DUI populations.