Trends in the number of traffic accident victims on Brazil's federal highways before and after the start of the Decade of Action for Road Safety.

This study aimed to analyze the trend in the number of fatalities, severe injuries, and minor injuries from traffic accidents on Brazil's federal highways according to the country's major geographic regions before and after the start of the Decade of Action for Road Safety (DARS). This was an interrupted time series study of data on accidents with fatal or injured victims provided by the Brazilian Federal Highway Police from 2007 to 2017. The Prais-Winsten method was used to calculate the monthly percentage change (MPC) in the number of fatalities, severe injuries, and minor injuries. Before the DARS, there was an upward monthly trend in the number of fatalities in these accidents in the country as a whole (MPC 0.71%) and in all five regions, especially in the South (MPC 1.01%) and Central-West (MPC 0.84%). There was an inverse trend after the start of the DARS, with a significant decrease in Brazil as a whole (MPC -1.24%) and in the major geographic regions. For each person that dies in an accident on a federal highway, at least 12 others suffer non-fatal injuries. There was an upward trend in the number of victims with severe injuries (MPC 0.53%) and minor injuries (MPC 0.8%) in Brazil and in the major geographic regions in the period prior to the DARS. After the start of the DARS, there was a significant downward trend in the absolute frequencies of these outcomes at the national and regional levels. In conclusion, before the DARS, there was an upward monthly trend in the number of fatal and injured victims of traffic accidents on Brazil's federal highways. After the start of the DARS, in 2011, there was an inverse trend, namely a decline in these outcomes in the country.