Enforcement or incentives? Promoting safety belt use among military personnel in the Netherlands.

During a nationwide campaign to promote safety belt use among military personnel, a field study was conducted at 12 different military bases in the Netherlands. Amount of enforcement, type of publicity, and incentive strategies were varied among military bases. Observations of safety belt use among servicemen in their personal vehicles were conducted before the campaign, immediately following the campaign, and 3 months later. Safety belt use increased from 65% during baseline to 73% directly after the campaign and to 76% 3 months later. An overall 28.6% increase in safety belt use (from 63% to 81%) was observed at seven bases, whereas no changes were found at five bases (68% on all occasions). To a large degree the effects were due to a 37.7% increase among young drivers. These results confirmed that enforcement, as well as incentives, can be effective in promoting safety belt use. However, treatment effects were not systematic, thereby complicating the interpretation of the results. Implications of these varied outcomes are discussed.