Cost-effectiveness of Periodic Motor Vehicle Inspection (PMVI): A review of the literature : A.C. Wolfe and J. O'Day, University of Michigan, Transportation Research Institute, Ann Arbor, MI, January 1985. NTIS No. DOT HS 806 750

Abstract

The purpose of this review of 41 studies and reports concerning periodic motor vehicle inspection was to seek evidence as to whether the costs of requiring all motorists to have certain safety components on their vehicles inspected and repaired on a regular basis are less than the benefits gained from such inspections in terms of safer vehicles and fewer vehicle-defect accidents. A number of studies provide evidence that vehicles in some PMVI jurisdictions are in better condition on some components than vehicles in some non-PMVI jurisdictions, but none of these studies involve truly random samples of vehicles-in-use. Similarly, a number of studies have reported some reductions in accidents in association with PMVI (and some have reported the opposite), but no credible evidence was found which demonstrates significant changes in vehicle-defect accidents as a result of PMVI. Thus the few studies which have addressed the cost-benefit question have tended to be rather subjective and speculative because of the shortage of thorough and believable research on PMVI effectiveness. There is credible evidence that existing PMVI programs are not as reliable in detecting degraded safety components and forcing their repair as was envisioned by PMVI proponents. It is clear that much more could be done to improve the effectiveness of existing PMVI programs. Also auto manufacturers could do more to encourage the maintenance of safe vehicles by providing durable components and built-in indicators of their failure.