The relative influence of alcohol and seatbelt usage on severity of injury from motor vehicle crashes.

Seatbelt usage has been consistently documented to decrease mortality and injury severity from motor vehicle crashes (MVC); however, conflicting results are available comparing mortality and injury severity, and blood alcohol positivity. Prospective testing on all MVC admissions showed that 51.5% of the non-belted, and 22% of the shoulder-belted drivers had a positive blood alcohol content (p less than 0.001). A comparison of belted and non-belted MVC drivers revealed a significantly higher mean length of stay (LOS) (p less than 0.05) and Injury Severity Score (ISS) (p less than 0.01) for the non-belted drivers. A comparison of groups positive and negative for blood alcohol revealed no significant differences in LOS or ISS, suggesting that these parameters are related to seatbelt use and not alcohol consumption.