Abstract
The objective of this study was to determine the effects the Alabama automotive diagnostic inspection facility (Auto Check) has had on the accident rate of Huntsville residents who had accidents in Madison County. The inspected vehicles had a significantly lower accident rate than the uninspected vehicles. The Auto Check accident rates were adjusted for sex, age and ZIP. A comparison of the Auto Check participant with the driver involved in an accident indicates that the person bringing the car to Auto Check for the first periodic inspection is probably not the principal driver.