Factors contributing to the decline in the number of heavy goods vehicles involved in injury accidents in Norway from 2007 to 2020

Abstract

There has been a large decline in the number of police reported injury accidents on public roads in Norway after 2007. The decline has been particularly large for accidents involving heavy goods vehicles. From 2007 to 2020, the number of heavy goods vehicles involved in injury accidents declined by 68%. The total number of injury accidents declined by 56%. The study presented in this paper aimed to identify factors explaining the decline from 2007 to 2020 in the number of heavy goods vehicles involved in injury accidents in Norway. This is done by reconstructing annual changes in factors known to influence the number of accidents and estimating the potential impacts of changes in these factors. The factors identified can only be regarded as potential causes, as the study design does not permit causal inferences. In total, 14 factors were identified. For 12 factors numerical estimates of the contributions to the declining trend were developed. The combined contribution of all factors accounted for 32.6%–37.5% of the decline in the number of heavy vehicles involved in injury accidents. More than 60% of the decline is not accounted for and must have been caused by factors not included in this study.