A delayed reward strategy for large-scale motivation of safety belt use: A test of long-term impact

An incentive program applicable for communitywide motivation of safety belt use was implemented at a large industrial complex. After four weeks of daily baseline observation of drivers' shoulder belt usage at two entrance/exit gates during employees' afternoon departure, an incentive intervention was implemented at only Gate 1, where it was impossible to stop vehicles and immediately reward safety belt wearing. Instead, the employees were informed via signs, posters, and newspaper articles that a winning license plate number would be randomly selected each day from among those vehicles exiting Gate 1 whose drivers were wearing shoulder belts. Winners were offered the choice of two university basketball tickets or meals for two at a local restaurant. Shoulder belt observations continued daily at both gates throughout the three-week incentive intervention, and for three long-term follow-up phases over the subsequent eleven months. The incentive intervention influenced substantial increases in shoulder belt use (from a mean percentage of 6.3% belt usage during baseline to 23.1% during the incentive period); and affected some long-term impact (i.e. mean USE = 16.3% after one month, 15.8% after three months, and 11.0% after ten months).