New evidence on the life-saving value of PTI
On 9 September 2026, CITA hosted the webinar “New Evidence on the Life-Saving Value of PTI”, bringing together new empirical evidence on the contribution of PTI to road safety and its economic value.
The webinar was opened by Gerhard Müller, CITA President, and moderated by Richard Goebelt, Chairperson of CITA Topic Area C “External Affairs”. The two main presentations were delivered by Prof. Dr. Lars Hannawald, Managing Director at AFUS, who presented the key findings on the relationship between vehicle condition, inspection intervals and road safety, and Prof. Dr. Wolfgang H. Schulz, Professor of Economics, Mobility, Trade & Logistics at Zeppelin University, who presented the economic impact and cost-benefit assessment.
Technical defects increase significantly with vehicle age
Prof. Hannawald presented the results of a comprehensive study examining the actual technical condition of vehicles in road traffic, the role of technical defects in accidents and the potential of different PTI intervals to reduce accidents through 2035.
One of the study’s key strengths is its empirical approach. The assessment of vehicles in actual road traffic conditions covered 11,604 passenger cars, with their condition recorded before repairs and maintenance carried out in preparation for an upcoming PTI. The analysis showed a clear relationship between vehicle age and technical condition: the technical defect rate increased substantially as vehicles became older.
The results also highlighted the important preventive effect associated with PTI. Comparing vehicles in road traffic before PTI-related repair and maintenance with vehicles presented for inspection showed considerably higher defect rates in the former group. This indicates that the inspection cycle also encourages vehicle owners to identify and address defects before presenting their vehicles for PTI.
Technical defects are more relevant to accidents than official statistics suggest
A second part of the research analysed 2,429 passenger cars involved in traffic accidents, drawing on the DEKRA defect database. In these cases, accident experts assessed technical defects and classified them as contributing, possibly causal or causal to the accident.
The results are particularly significant: accident-relevant technical defects were identified in 6.4% of the analysed cases, ranking fifth among the causes of accidents documented by the police.
During the discussion, Prof. Hannawald explained why this figure differs considerably from police accident statistics. Police officers at an accident scene can generally identify only readily observable defects, whereas specialised accident reconstruction experts systematically investigate technically possible defects and assess their potential influence on the accident. This more detailed investigation provides a substantially broader picture of the role played by vehicle defects.
Shorter inspection intervals can reduce accident risk
The study also modelled the potential impact of changing PTI intervals. Using vehicle-age-related defect rates together with different scenarios for the development of the vehicle fleet, the researchers assessed the potential reduction in road traffic accidents through 2035.
For example, introducing annual PTI from the age of ten resulted in a modelled reduction potential for road traffic accidents with injuries in Germany ranging from 1.4% to 6.3% in 2035, depending on the fleet-development scenario considered.
These findings underline that inspection frequency becomes increasingly relevant as vehicles age and their probability of developing safety-relevant technical defects rises.
Road safety benefits also make economic sense
Prof. Wolfgang H. Schulz then presented an economic assessment building on the empirical findings of the Dresden research. The analysis examined a specific policy scenario: moving passenger cars aged ten years and above in Germany from biennial to annual technical inspection, assessing its costs and social benefits over the period 2024 – 2035.
The results showed a clear positive economic outcome. The headline analysis calculated a benefit-cost ratio of 1.86, with estimated benefits of EUR 22.6 billion, costs of EUR 12.2 billion, and consequently a net social benefit of approximately EUR 10.4 billion over the evaluation period. In other words, according to the study, every euro spent on the additional inspections generates almost EUR 1.9 in avoided social accident costs.
The economic analysis therefore complements the road safety findings: reducing the prevalence of technical defects through more frequent inspection of older vehicles can generate benefits that exceed the additional resources required for inspection.
At the same time, the economic assessment stressed that its conclusions should be interpreted within their defined scope. It supports a differentiated approach for older vehicle cohorts in countries with ageing fleets and established inspection infrastructures, rather than automatically supporting a uniform tightening of inspection requirements across all EU Member States.
Closing the webinar, CITA President Gerhard Müller highlighted three central messages emerging from the presentations: technical defects play a relevant role in accidents; PTI contributes to reducing the number of vehicles circulating with major defects; and the economic analysis demonstrates that PTI delivers benefits to society that exceed its costs.
The webinar therefore provided new empirical evidence supporting the role of PTI as an important road safety instrument. As Prof. Hannawald emphasised at the end of the discussion, future debates should be based on the right numbers and on a clear understanding of what the available evidence actually measures.
For CITA, these findings reinforce the importance of maintaining an evidence-based discussion on the future of vehicle roadworthiness inspection, particularly as vehicle fleets age and policymakers consider the appropriate balance between road safety, inspection requirements and costs to vehicle owners.