Rijden onder invloed in de provincie Groningen, 1993-1994 : de ontwikkeling van het alcoholgebruik van automobilisten in weekendnachten. In opdracht van Directoraat-Generaal Rijkswaterstaat, Adviesdienst Verkeer en Vervoer AVV en Directoraat-Generaal Rijkswaterstaat, Directie Noord-Nederland.

In October 1994, the SWOV Institute for Road Safety Research and six police control teams conducted a roadside survey. The aim was to establish the motorists' alcohol consumption in the Dutch province of Groningen. Blood alcohol content (BAC), age and sex of the drivers were collected and recorded. If the recorded BAC level was 0.7 or over, places of origin of the offenders were also collected and recorded. The study was carried out on Friday and Saturday nights. The 1994 sample included 1370 motorists. The results of the 1994 survey are compared with the results of the 1993 survey