An ambitious traffic enforcement project was launched in the Dutch province of Friesland in February 1998. This project includes an intensification of enforcement of speeding on provincial roads as well as intensified enforcement of seat belt use and driving while intoxicated. SWOV Institute for Road Safety Research drew up the starting plans for this project and is currently evaluating progress and results of the project. This report recounts a preliminary study that was conducted to determine the kind of data available or needed to conduct the evaluation. Some conclusions were: (1) The short-term and middle-term evaluation of the Frisian traffic project can be planned reasonably well; (2) For long-term evaluation it would in any case be possible to study relationships between police enforcement, driving speed on provincial roads, and accidents on provincial roads; (3) There are two real threats for the long-term evaluation: (a) the expected discontinuity in the police data; and (b) an insufficient variation in the level of police enforcement. Due to these threats, it cannot be stated with certainty at this time that a long-term analysis would be worthwhile; and (4) the importance of the long-term evaluation creates the need for measures to make this evaluation possible.
Abstract