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Establishment of the New Zealand Drivers Study.

AIM
Despite a significant improvement since graduated licensing was introduced, traffic related injury remains the leading cause of death and hospitalisation among young New Zealanders. The New Zealand Drivers Study (NZDS) was established with a view to providing information that would lead to an improvement in this situation. The NZDS is a prospective cohort study designed to explore the relationship between a comprehensive range of driving and traffic safety related factors and subsequent traffic crashes and convictions among newly licensed drivers. We describe key process objectives in establishing the cohort, and our success in meeting them and the implications arising thereof.


METHODS
We compare what occurred with what was proposed in the research protocol.


RESULTS
We successfully established a cohort of 3992 newly licensed car drivers with substantial heterogenity in sociodemographic, behavioural, and driving experiences. We have 825 Maori that will allow us to undertake a separate Maori analyses. Response rates to interviews at the restricted and full licence stages have been very high at 87% and 93%, respectively. We have been successful via linkage in following them through the stages of licensure and via linkage obtaining national data on the outcomes of interest.


CONCLUSIONS
The NZDS is well placed to make a significant contribution to our knowledge of young driver road safety behaviour. This process has already commenced.