Alcohol and drug use by Spanish drivers: Comparison of two cross-sectional road-side surveys (2008-9/2013)

- We investigated two separate representative samples of Spanish drivers.
- We compared the use of alcohol and drugs by drivers.
- Alcohol was analyzed in breath air and drugs in oral fluid.
- A decrease in the use of drugs was observed after introducing screening of drugs.
- Deterrence depends on the frequency of the roadside testing and other factors.