Effectiveness of Safe Routes to School

Peter Muennig at Columbia's Mailman School of Public Health described an evaluation of a Safe Routes to School programme in New York City,1 online 15 May 2014). Federal funding enabled the city to change many dangerous intersections near 100 public schools. They extended sidewalks, set off dedicated bicycle lanes, installed speed humps and changed timing lights to give pedestrians more time to cross. It is estimated the $10 million investment will yield a $230 million benefit and add 2055 quality-adjusted life years. These estimates are based on injuries prevented and include the assumption that the safety benefit would last for about 50 years. The authors used data on intersections before, during and after modifications were made to reach these conclusions.

Driving after marijuana use

Investigators in Massachusetts and Washington found that 30% of male and 13% of females college students surveyed used marijuana and about 65% drank alcohol in the preceding month.2 Nearly half the men but only 9% of women drove after using marijuana, believing it to be safe. The researchers noted that ‘although a higher proportion of students had drunk alcohol in the past month, rates of driving were much lower after drinking than after marijuana use.’ They conclude, ‘our study quantifies the prevalence, which is useful in setting priorities for public health action.’ The authors also believe the findings ‘… supplement our knowledge that use increases the risk of motor vehicle crashes’.

Editor’s comment: I have yet to see good evidence that the first assumption is correct and found no evidence in the report of an increased risk with marijuana.

Drunk driving crashes involving child deaths

About 20% of the 1210 children under 15 in the USA who were killed in a car crash in 2010 involved drunk driving. Quinlan and colleagues in Chicago report in Pediatrics3 that most children who die in these …