The truth about Seat Belt use among Hispanics.

While seat belts reduce by about 50 percent the risks of injuries and deaths in motor vehicle crashes, results from more than a dozen studies of seatbelt use disparities between Hispanics and non-Hispanics over the years have been strikingly inconsistent. In the December 2006 issue of Injury Prevention, a leading international peer reviewed journal for health professionals and others interested in all unintentional injuries, Meharry-State Farm Alliance researchers at Nashville’s Meharry Medical College reconciled the inconsistencies. In so doing, the authors, led by epidemiologists Nathaniel C. Briggs, M.D., opened a window of opportunity for promoting safe driving practices among the Hispanic immigrants arriving in the United States every year.

The Meharry-State Farm study of seat belt use disparities by Hispanic ethnicity is the largest investigation of its kind conducted to date. Utilizing data from the Fatality Analysis Reporting System, a U.S. population-based archive of information on motor vehicle crash fatalities maintained by the National Highway Traffic Safety Administration (NHTSA), the Alliance researchers looked in-depth at seat belt use in a study population of 60,758 non-Hispanic whites and 6,879 Hispanics killed in motor vehicle crashes from 1999-2003. Unlike previous reports the Meharry-State Farm study took Hispanic sub-groups of national origin into account by investigating seat belt use disparities separately for Mexican Americans, Central Americans-South Americans, Puerto Ricans, and Cubans, who collectively comprise 93.5 percent of U.S. Hispanics.

Results of the Meharry-State Farm study show that seat belt use for each Hispanic sub-group of origin was as prevalent, or more prevalent, compared to non-Hispanic whites. But marked variations in seat belt use were as evident across the four sub-groups. For example, differences in seat belt use among Puerto Rican and Cuban Hispanics relative to non-Hispanic whites were statistically insignificant. But among Mexican American Hispanics, seat belt use was 33 percent more prevalent than among non-Hispanic whites. And Central American-South American Hispanics were 66 percent more likely to use seat belts than non-Hispanic whites. The associations for Mexican American and Central American-South American Hispanic subgroups were highly statistically significant.

For each Hispanic sub-group of national origin, the Meharry-State Farm Alliance researchers looked at seat belt use stratified by age group, sex, median household income (quartiles), seat position (driver vs passenger), region (urban vs. rural) and state seat belt law (primary vs. secondary). Among Puerto Rican and Cuban Hispanics, the prevalence of seat belt use was comparable to that of non-Hispanic whites.

Among the Mexican American and Central American-South American Hispanic sub-groups, a common pattern emerged. For these sub-groups, the magnitude of increased seat belt use relative to non-Hispanic whites was greatest among Hispanic motorists who were less than 49 years of age, men in the bottom income quartile, and drivers in rural areas and in primary law states.

The Meharry research team speculated that the relative increase in seat belt use among Mexican American and Central American-South American Hispanics reflected immigrant status, given the predominance of both sub-groups among the waves of Hispanic émigrés recently arriving in the U.S. Most notably, the undocumented status of many Mexican American and Central American-South American Hispanic émigrés was suggested as a potentially important contributor to the unusually high prevalence of seat belt use.

Seat belt use is much less prevalent in Hispanic-speaking countries than in the U.S., and the Meharry-State Farm Alliance researchers offered a plausible explanation for the irony. As Dr. Briggs noted, “A greater adherence to seat belt laws among undocumented Central/South American and Mexican American motorists compared with Whites could reflect greater concerns about being stopped by law enforcement officers. This is consistent with our finding that, among both Hispanic sub-groups, the [prevalence] of seat belt use was much higher in states with primary enforcement seat belt laws than in states with secondary enforcement laws.”

Because English literacy among Hispanic émigrés is often poor and both roadways and traffic laws in the U.S. are more complex than in Hispanic countries south of the U.S. border, Meharry-State Farm Alliance researchers noted that belted motorists who are immigrants may contribute heavily to the increased motor vehicle crash fatality rates documented among Hispanics; and this could reflect a lack of familiarity with the law, rather than deliberate noncompliance.

As a corollary, the Meharry research team underscored an important implication of the study findings, noting: “If immigration status is associated with making a special effort to buckle up in order to avoid confrontation with law enforcement officer, then interventions to increase awareness about less easily understood driving laws (e.g., the relation between blood alcohol concentration and driving under the influence) might be particularly effective early in the acculturation period of Hispanic immigrants…”