Impaired Driving Study
This document presents the results of a comparison of ID crashes compared to non-ID crashes over a recent three year period (FY2015-2017). An over-represented value of an attribute is a situation found where that attribute has a greater share of ID crashes than would be expected if it were the same as that same attribute in non-ID crashes. That is, the non-ID crashes are serving as a control to which the ID crashes are being compared. In this way anything different about ID crashes surfaces and can be subjected to further analyses.