Article

IT'S NO ACCIDENT: EVALUATING THE EFFECTIVENESS OF VEHICLE SAFETY INSPECTIONS: EVALUATING VEHICLE INSPECTIONS

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Abstract

An increase in technology means that vehicles are more reliable than in the past. Accordingly, states have begun to discontinue their requirements for vehicle safety inspections. To gauge the effect of such changes, we examine traffic fatality data from 2000 to 2015, with emphasis on New Jersey, which ended safety inspection requirements in 2010. Utilizing a synthetic controls approach, we conclude that ending these requirements did not result in a significant increase in the frequency or intensity of accidents due to car failure, implying that the consumer and government expenditures used for inspections could be reallocated to other areas of travel safety. (JEL R41, Z18, C23)

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... However, novel technologies and advances in traffic safety in recent years have led to declines in road crash rates, and as a result, some countries or regions within countries have opted to abolish this legal requirement [7,8]. According to reports by the National Highway Traffic Safety Administration in the USA, the risk of road crashes associated with driving a vehicle manufactured before 2000 is 71% higher than for vehicles manufactured in 2010 and later [9]. ...
... It appears evident that maintaining mandatory VTI should be backed by evidence of its efficacy in reducing road crashes, rather than solely by theoretical arguments, based on its proven usefulness in detecting (and correcting, when necessary) vehicle defects potentially associated with a greater risk of causing road crash [2,[4][5][6][7][8]. In principle, the high cost of maintaining specialized testing and inspection centers and the contradictions among classic review articles available to date would appear not to justify the implementation of systematic inspections. ...
... Many of the articles reviewed here, especially among older ones, reported ecological studies in which the unit of study was not vehicles or drivers but administrative bodies (states, counties, etc.). These studies are based on comparing crash rates among entities with different levels of implementation of VTI programs [7,8,[21][22][23][24]. As noted above, the causal evidence these studies provided was weak given that they were potentially affected by the well-known issue of ecological fallacy [11,12]. ...
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This systematic review was conducted to determine the effect of periodic motor vehicle inspections on road crashes and injuries, compared to less exposure to periodic inspections or no inspections. The Medline, Web of Science, and Scopus databases were used to search the literature. Ecological studies were specifically excluded. A reverse search of the results with these databases and of other identified narrative reviews was also performed. Of the 5065 unique references initially extracted, only six of them met the inclusion criteria and were selected for review: one experimental study, two cohort studies with an internal comparison group, two cohort studies without a comparison group, and one case–control study. Two authors independently extracted the information and assessed the quality of each study. Due to the heterogeneity of the designs and the intervention or comparison groups used, quantitative synthesis of the results was not attempted. Except for the case–control study, which showed a significant association between road crashes and the absence of a valid vehicle inspection certificate, the other studies showed either a small reduction in crash rates (around 9%), no association, or a higher crash rate in vehicles with more inspections. In all observational studies, the risk of residual confounding bias was significant and could have explained the results. Therefore, although the research reviewed here suggests that periodic inspection may be associated with a slight reduction in road crashes, the marked heterogeneity along with probable residual confounding in most reports prevented us from establishing causality for this association.
... As a very high degree of correlation between the results of technical inspections given by the percentage rate of temporary roadworthiness and non-worthiness of vehicles and the number of traffic accidents due to vehicle technical errors with a statistically significant linear relationship was demonstrated, it was possible to vehicles are a cost-effective way to increase the road safety [25]. In particular, the analysis of changes in technical control procedures (in the US called security inspections), carried out in the US in 2017, raised many doubts about the effectiveness of these controls. ...
... In particular, the analysis of changes in technical control procedures (in the US called security inspections), carried out in the US in 2017, raised many doubts about the effectiveness of these controls. According to the above analysis, the number of fatal accidents due to vehicle technical defects has been steadily decreasing over the last two decades, as well as due to the safer technology of newer vehicles [25]. However, the economic dimension plays a major role in this, because periodic technical inspections and subsequent repairs of vehicles represent financial costs for the inhabitants of the given states and thus their abolition, i.e. their absence is a politically popular topic. ...
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The article presents a search for links between the Periodic Technical Inspections of Vehicles (TI) and traffic accidents due to vehicle technical defects in the Slovak Republic. Based on these links, it is sought to assess the justification for TI regarding the road safety. For this purpose, statistical data on traffic accidents, caused by vehicle technical defects as well as data concerning TI carried out were examined. The first finding was that the approaching end of the validity of the TI, the probability of traffic accidents due to technical defects increases for vehicles. The second finding was that with the increasing number of vehicles assessed at the Periodical Technical Inspection Stations (PTI) as temporarily roadworthy and not roadworthy, the number of accidents due to vehicle technical defects was decreasing. The results formulated in this paper show that the TI have a measurable effect on traffic accidents caused by vehicle technical defects, thus positively affecting the road safety and thus having a demonstrable justification.
... Hoagland and Woolley. opposed the continuation of the inspection program as well (15). Utilizing a synthetic controls approach examining traffic fatality data from 2000 to 2015 on New Jersey (ended safety inspection requirements in 2010), the study concluded that ending the mandatory inspection program did not result in a significant increase in the frequency or intensity of crashes resulting from car failure (15). ...
... opposed the continuation of the inspection program as well (15). Utilizing a synthetic controls approach examining traffic fatality data from 2000 to 2015 on New Jersey (ended safety inspection requirements in 2010), the study concluded that ending the mandatory inspection program did not result in a significant increase in the frequency or intensity of crashes resulting from car failure (15). ...
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The National Highway Traffic Safety Administration’s (NHTSA) guideline on state motor vehicle inspection programs recommends that states should maintain a vehicle safety inspection program to reduce the crash outcomes from the number of vehicles with existing or potential conditions. Some states have started to terminate the vehicle safety inspection program because of insufficient effectiveness measures, budget constraints, and modern safer automobiles. Despite the consensus that these periodic inspection programs improve vehicle condition and improve safety, research remains inconclusive about the effect of safety inspection programs on crash outcomes. There is little recent research on the relationship between vehicle safety inspection programs and whether these programs reduce crash rates or crash severities. According to the 2011-2016 Fatality Analysis Reporting System (FARS) data, nearly 2.6 percent of fatal crashes happened due to vehicle’s pre-existing manufacturing defects. NHTSA’s vehicle complaint database incorporates more than 1.4 million complaint reports. These reports contain extended information on vehicle-related disruptions. Around five percent of these reports involve some level of injury or fatalities. This study used these two databases to determine the effectiveness of vehicle inspection regulation programs in different states of the U.S. A statistical significance test was performed to determine the effectiveness of the vehicle safety inspection programs based on the states with and without safety inspection in place. This study concludes that there is a need for vehicle safety inspections to be continued for the reduction of vehicle complaints.
... Hoagland and Woolley. opposed the continuation of the inspection program as well (15). Utilizing a synthetic controls approach examining traffic fatality data from 2000 to 2015 on New Jersey (ended safety inspection requirements in 2010), the study concluded that ending the mandatory inspection program did not result in a significant increase in the frequency or intensity of crashes resulting from car failure (15). ...
... opposed the continuation of the inspection program as well (15). Utilizing a synthetic controls approach examining traffic fatality data from 2000 to 2015 on New Jersey (ended safety inspection requirements in 2010), the study concluded that ending the mandatory inspection program did not result in a significant increase in the frequency or intensity of crashes resulting from car failure (15). ...
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According to 2010–2014 Fatality Analysis Reporting System (FARS) data, nearly 6.35% of fatal crashes happened as a result of vehicles’ pre-existing manufacturing defects. The National Highway Traffic Safety Administration’s (NHTSA) vehicle complaint database incorporates more than 1.37 million complaint reports (as of June 1, 2017). These reports contain extended information on vehicle-related disruptions. Around 5% of these reports involve some level of injury or fatalities. This study had two principal objectives, namely (1) perform knowledge discovery to understand the latent trends in consumer complaints, and (2) identify clusters with high relative reporting ratios from a large contingency table of vehicle models and associated complaints. To accomplish these objectives, 67,201 detailed reports associated with injury or fatalities from the NHTSA vehicle complaint database were examined. Exploratory text mining and empirical Bayes (EB) data mining were performed. Additionally, this study analyzed five years (2010–2014) of FARS data to examine the research findings. Results show that major vehicular defects are associated with air bags, brake systems, seat belts, and speed controls. The EB metrics identified several key ‘vehicle model with major defect’ groups that require more attention. This study demonstrates the applicability of consumer complaints in identifying major vehicular defects as well as key groups of ‘vehicle model with major defect.’ The findings of this study will provide a significant contribution to the reduction of crashes from vehicle-related disruptions. The research presented in this paper is crucial given the ongoing advancement of connected and automated vehicle technologies.
... However, Hoagland and Woolley suggested that improvement in the reliability and technology of modern vehicles reduces the need for an effective vehicle inspection. To reach to this conclusion, they analyzed the effect of eliminating vehicle inspection in the state of New Jersey and found no significant increase in accidents due to detected vehicle defects [5]. ...
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On 20 May 2018, Royal Decree 920/2017, establishing the minimum requirements for the regime of the vehicle technical inspection (ITV in Spanish) to circulate on public roads, entered into force. The new regulations are aimed at ensuring that vehicles in general, and agricultural vehicles in particular, are in proper condition from the point of view of safety and environment. In La Rioja, detailed data are available on the technical inspections performed on agricultural machinery for the last 15 years (2005–2020). The aim of this paper is to analyze the possible effects of technical inspections of agricultural vehicles on their environmental impact. Emissions regulations for this type of vehicle have evolved over the last few years, and as a result, new tractors have better environmental performance. Considering that serious defects detected in vehicle technical inspections can lead the owner to replace the vehicle with a new one, there is a potential reduction in the environmental impact associated with ITVs, as studied in this paper.
... The final PTI product is therefore an evaluation of the technical condition of the vehicles [59]. However, the provision of this service is not a normal business but the safeguarding of the state's interest [60]. For this reason, the statistical results of technical inspections, given in particular the temporary roadworthiness and not roadworthiness of vehicles for road traffic, are closely monitored by the PTI inspection authorities and are considered as an indicator of the quality of the given PTI. ...
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This article deals with the minimum requirements for quality management at Periodical Technical Inspection Stations (PTIS) for road vehicles in the Slovak Republic, as well as in selected countries of the European Union. Specifically, it contains research performed at all of the PTIS in the Slovak Republic with a focus on the established quality management system and the number of employees of companies operating these PTIS, as well as similar research in selected countries of the European Union. Based on the research results, the article contains an assessment of the influence of the implemented quality management system on the operation of PTIS. The analysis of the results showed that 86.7% of PTIs have an established system to meet the minimum requirements for quality management through a documented procedure (internal regulation), and 13.3% of the PTI have the certified quality management system according to the STN EN ISO/IEC 9001 standard. Unfortunately, no PTI in the Slovak Republic has the fulfilment of quality management requirements according to the standard STN EN ISO/IEC 17020.
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Synthetic control methods for comparative case studies: Estimating the effect of California's tobacco control program
  • A Abadie
  • A Diamond
  • J Hainmuller
Abadie, A., Diamond, A., & Hainmuller, J. (2010) Synthetic control methods for comparative case studies: Estimating the effect of California's tobacco control program. Journal of the American Statistical Association, 105, 493-505.
The Synthetic Control Method as a Tool to Understand State Policy
  • R Mcclelland
  • S Gault
McClelland, R., & Gault, S. (2017). The Synthetic Control Method as a Tool to Understand State Policy.