Abstract
In New Zealand, Periodic Motor Vehicle Inspection (PMVI) renewal dates of accident involved vehicles were collected routinely as part of the accident reporting system.Accident involved vehicles were analysed by age and time since the most recent inspection. The observed probability of accident involvement over a short time interval was found to increase with the time since last inspection for (A) the first analysis (B) old cars in the second analysis. These results fo not necessarily imply that PMVI is cost effective, but the method could provide a basis for determining the optimal time between inspections.