Over the last few years the NZ Transport Agency, NZ Police and the Ministry of Transport have been working to improve how road crash information is recorded, processed and then provided to the road safety community. As you may know there have already been some changes. The NZ Police now submit crash information electronically via iPhones and we are maximising this data by improving and modernising CAS through the CAS replacement project.
Alcohol suspected (July 2017)
Previously we let you know that, since July 2016, we have noticed a sharp increase in alcohol related crashes recorded in CAS. Alcohol related crashes include crashes where alcohol is suspected but we do not have a breath/blood alcohol result (factor 101), and where an alcohol test has shown the driver to be over the limit or where a test was refused (factor 103). We noted that the increase was being driven by a sharp increase in factor 101 ‘alcohol suspected’.
NZTA and NZ Police have been investigating what is driving this trend and are now able to advise that this is due to:
- Understanding how business rules around alcohol suspected cases are applied and interpreted between NZTA and NZ Police
- Since NZ Police moved to electronic data collection, Traffic Crash Reports are received by NZTA quicker and fewer crashes with alcohol suspected have subsequently been updated with a blood or breath alcohol result.
These crashes remain 101 ‘alcohol suspected’ as opposed to being recoded as a 102 -‘alcohol test below limit’ or 103 –‘alcohol test above limit or test refused’. NZTA and NZ Police are working together to implement a common understanding of alcohol suspected, and to ensure alcohol crashes are updated, and are taking steps to bring this data up to date with the receipt of more alcohol test results.
As we receive these some 101 codes will change to 103 and some to 102 (alcohol test below limit). Because of this, care should also be taken when analysing codes 102 and 103.In the meantime, we would suggest that you exclude 101’s from your analysis if it is possible for you to do so.