Predictors of seatbelt use in American Indian motor vehicle crash trauma victims on and off the reservation.

OBJECTIVES: American Indians (AI's) have the lowest rate of seatbelt use in the nation, putting them at significant risk for motor vehicle crash (MVC) morbidity and mortality. This study compares seatbelt use in victims of level one trauma crashes presenting from on and off AI reservations. Predictors of seatbelt use were evaluated as well. We hypothesized that AI's in crashes on a reservation would have lower rates of seatbelt use, even compared to AI's in crashes from off the reservation.

METHODS: This is a retrospective cohort study of consecutive MVC victims presenting to a level one trauma facility in Phoenix, Arizona from July 2003 to June 2005. Inclusion criteria were age >11 and transported directly from the crash; struck pedestrians were excluded. Inter-facility transports were also excluded, as these patients would likely represent a sicker population, possibly introducing bias. Characteristics of those patients (sex, race, location of crash, alcohol and seatbelt use) were analyzed in univariate and multivariate logistic regression.

RESULTS: Data were collected on 2339 patients. Three hundred ninety-two were excluded, leaving 1947 (83%) available for analysis. AI's had lower rates of seatbelt use compared to all other races. Additionally, AI's on a reservation were less likely to wear seatbelts than those off a reservation (25.9% versus 42.7%). However, when tested in a multivariate analysis with alcohol as a covariate, race and location became insignificant. Low seatbelt use by AI's on the reservation was primarily associated with alcohol use.

CONCLUSION: In this analysis, alcohol, rather than race or location, is the overriding predictor of seatbelt use. This study compared patients that were in crashes, and only those triaged to a level one trauma facility. If we assume unbelted passengers are more severely injured, this would bias our results. The application of these data may help direct future public service efforts to increase seatbelt use in target populations.