By passing legislation in 2006 to mandate primary enforcement of the Kentucky state law requiring safety belt use for motor vehicle occupants, the state could expect to realize an overall savings of at least $118 million in direct medical costs over the ten-year period from 2006 to 2015. Charges to Medicaid over that period would be about $34 million less than under the current secondary enforcement model. In addition, there would be at least $67 million saved in medical costs to commercial insurers, $2.3 million to Medicare, $3.3 million to Worker’s Compensation, and $11.2 million to other sources.

These savings would be a direct result of an increase in the number of Kentuckians who would wear a safety belt if a primary enforcement law were in place. States that have enacted primary enforcement legislation in the past have experienced increases in safety belt use of as much as 18 percentage points. The National Highway Traffic Safety Administration (NHTSA) has stated that the average increase is between 10 and 15 percentage points. The savings given above assume that Kentucky would experience an increase of 13 percentage point s, which would move the state’s usage rate from 67 percent to 80 percent, which was the national average in 2004.

NHTSA has published estimates of the effectiveness of safety belts in preventing fatal and nonfatal injuries. The estimated effectiveness varies depending on the type of vehicle in which the occupant is riding (passenger car versus light truck), the type of safety belt used (lap belt only versus lap and shoulder belt ), and the occupant’s position in the vehicle (front seat versus rear seat). Linked collis ion report and hospital discharge data from Kentucky’s Crash Outcome Evaluation System (CODES) were used to estimate Kentucky’s overall safety belt effectiveness for preventing moderate-to-critical injury at 55 percent. This number was then used to calculate medical costs savings for Kentucky’s Medicaid program and other payers that would result from enactment of a primary enforcement law. Particular attention was given to traumatic brain injuries (TBI) and spinal cord injuries (SCI) because they often result in medical costs for years after the original injury.

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The contents of this report reflect the views of the authors, who are responsible for the facts and accuracy of the data presented herein. The contents do not necessarily reflect the official views or policies of the University of Kentucky, the Kentucky Transportation Cabinet, or the Federal Highway Administration. This report does not constitute a standard, specification, or regulation. The inclusion of manufacturer names or trade names is for identification purposes only and are not considered as endorsements.