[Risk factors for injuries caused by traffic accidents and the impact of an intervention on the road]. / Factores de riesgo de lesión por accidentes de tráfico y el impacto de una intervención sobre la carretera.

OBJECTIVE: To evaluate the effect of interventions at a highway, in the occurrence and severity of injuries by traffic accidents. METHOD: It was made a comparative analysis of two cross-sectional studies in 1994 and 1996. RESULTS: In 1994 the rate was 7.96 accidents/ 100,000 vehicles and in 1996 8.49 / 100,000 vehicles. The increase was not significant (p>0.05). The rate of injured drivers in 1994 was of 2.10 / 100,000 vehicles and of 1.35 / 100,000 vehicles in 1996, which was a significant decrease (p<0.000). The self-report of use of seat belt (63.46% versus 76.6%), the small vehicles involved in accidents (7.9% versus 37.7%), nocturnal schedule (23.7% versus 31.8%) and in Mexico-Cuernavaca direction (45% versus 66.7%), were more frequent in 1996 (p<0.05). The risk of injury, using a logistic regression model, between drivers exposed to the interventions (1996) and those that were not exposed (1994) adjusted by: age, speed, use of seat belt, alcohol intake and external cause, showed a protective effect of the interventions at the highway (OR 0.42 CI95% 0.27-0.66). CONCLUSION: There is an evident need of multisectorial approaches in the study and evaluation of the interventions in the field of the traffic accidents. The present research is a clear example of the repercussions over health of interventions developed by the transportation sector at the highway.

[Safety belt use and severity of injuries in traffic accidents]. / Cinturón de seguridad y gravedad de lesiones en accidentes de tráfico en carretera.

OBJECTIVE: To analyze the association between the severity of car accident injuries and the use of safety belts. MATERIAL AND METHODS: The unit of observation and analysis was car drivers in the Mexico-Cuernavaca toll highway. Variables included were those of car drivers, the vehicles and the physical environment at the accident site. Statistical analysis was carried out by means of chi square, odds ratios, 95% confidence intervals and logistic regression. Data was collected in 422 questionnaires for 324 accident events. RESULTS: There were 177 injured people, including 12 deaths, with rates of 67.5 injuries and 4.58 deaths per 10 000 kilometers driven. Variables associated with not using a safety belt (p < 0.05) were: alcohol drinking, vehicle size, night-time and road section. Risk factors for severe injuries were: not using a safety belt (raw OR 4.9, 95% CI 2.2-10.8, adjusted OR 2.94, 95% CI 1.13-7.66); age < 25 years (OR 3.6, 95% CI 1.0-12.7) and > 54 (OR 6.0, 95% CI 1.4-25.0); alcohol drinking (OR 10.8, 95% CI 3.8-30.4); and night time (OR 2.8, 95% CI 1.4-5.8). CONCLUSIONS: Theses findings suggest the need to formulate interventions aimed at enforcing the use of safety belts and prevention of related factors.