This report summarizes and synthesizes the findings of two complementary studies conducted to investigate factors related to enhanced seat belt reminder (ESBR) effectiveness and acceptance. It also provides recommendations for ESBR design and suggests a conceptual rating system for ESBRs. A field observational study found that belt use rates of drivers in vehicles with most types of ESBR systems was about 3 to 4 percentage points higher than drivers in vehicles without ESBRs, whose observed belt use rate was 85 percent. The most significant increases in belt use were found among occupant groups with the lowest belt use propensities. A separate system feature study experimentally compared alternative seat belt reminder systems and displays to determine which systems and components drivers find to be most effective, attention-getting, annoying, and desirable. Systems with more aggressive reminder displays and more frequent repetition patterns were perceived to be the most effective, and sounds were perceived to be more effective than visual displays. Perceived effectiveness and annoyance of individual displays were strongly correlated. There is good agreement between the two studies on the association of a greater likelihood of seat belt use with ESBR systems in general and the importance of including an auditory component to the system. Belt use rates based on averaging estimates for age/gender groups were strongly correlated according to system features. Based on the findings of these two studies, together with other literature, a set of recommendations for effective ESBR design are provided. Based on these criteria, a conceptual rating scheme was developed to provide a numeric figure-of-merit for ESBR systems. The rating scheme is preliminary and will require validation before use. (Author/publisher)
Abstract