Background Road crashes are a severe problem in low and middle-income countries, especially in Nigeria, and are a human tragedy. The Global Status Report on Road Safety 2023 shows that annual road traffic deaths have fallen slightly to 1.19 million. However, Road traffic injuries remain the leading killer of children and young people aged 5–29 years. More than half of fatalities occur among pedestrians, cyclists, and motorcyclists, in particular those living in low and middle-income countries (LMICs).

The primary purpose of the research-based, in-depth crash investigation is to identify in detail as many factors as possible that contribute to crashes and the resulting injuries, in particular, factors that have not previously been identified.

Objective To carry out the vehicle crash causation through in-depth vehicle crash investigation.

Methods This study uses an on-the-scene, in-depth crash investigation methodology from the European Commission’s DaCoTA online manual. The study reviews previous and current studies of crash investigation structures in Nigeria. It involves studying historical crash data from the Nigeria Bureau of Statistics (NBS) and Federal Road Safety Commission (FRSC), identifying high-risk areas, and assessing the common types of crashes. Data on the numbers and types of crashes occurring are needed to identify and order priorities and understand the problem’s scale.

Results The study results indicate that the current crash investigation structures in low and middle-income countries, like Nigeria, need to be more comprehensive in providing detailed information on the various factors that cause vehicle crashes and the resulting injuries like their counterparts in high-income countries.

Conclusions The main conclusion of the study is that, in principle, the in-depth vehicle crash investigation methodology plays a crucial role in improving road safety and reducing the number of crashes. This study provides a real-world perspective on injuries and fatality trends in vehicle crashes in Nigeria and effective vehicle crash investigations through close collaboration among various stakeholders, including law enforcement, healthcare professionals, transportation authorities, civil societies, and researchers. This study also examines the structures that utilize crash data to improve safety and compares the existing systems in LMICs with those of high-income countries.