This study looks at the prevalence of drug use by drivers on New Zealand roads. The driving populations considered are biased populations and the
results that have been obtained can be considered only as indicators of possible drug use in the wider driving population.
The driving populations considered in this study are:
- Sample one: Drivers killed as a result of a crash over the period of 1 July 2004 to 30 June 2009, and;
- Sample two: Drivers not involved in crashes but who had an evidential blood sample taken for alcohol analysis. The blood samples were collected over a six month period.