By Jeannette Bylov, AAU Communication and Public Affairs
Photo: Colourbox 

The traffic research group from the BUILD (Department of the Built Environment) at Aalborg University (AAU), together with researchers from the Center for Prehospital and Emergency Research at Aalborg University Hospital, Aalborg Municipality, and the Accident Analysis Group at Odense University Hospital, have investigated how data on ambulance calls can improve preventive work and increase road safety. The findings suggest that the number of traffic accidents on municipal roads may be significantly higher than previously estimated.

In the project, researchers identified the accident locations for all injured persons transported to the hospital by ambulance by correlating the ambulance call address with the patient's destination at the hospital.

The project has used ambulance calls in Aalborg Municipality from 2016 to 2019 to map out where the accidents happened for the injured persons who arrived at the hospital by ambulance. Precisely 3,358 traffic accidents occurred during this period. That is approximately four times as many as the police reported and located during the period.

Provides a more accurate picture

By incorporating data from the ambulance service and merging it with the existing police data for the same geographical areas, the researchers have managed to uncover dark figures that change accident statistics and show that there are far more accidents on the roads than previously assumed.

- Our figures show that there is likely more than a tripling in the number of traffic accidents in Denmark. Therefore, it would make a lot of sense to implement the new method in the municipalities' preventive work to secure the roads nationwide, says Harry Lahrmann, head of the project and Associate Professor at the department BUILD at AAU.

Uncovering dark figures has provided a more accurate picture of where most accidents occur, allowing municipalities to better prioritize work where they get the most road safety for their money.

- The project reveals that 55 per cent of accidents resulting in serious injuries took place away from major roadways, with a notable concentration of single accidents involving cyclists and pedestrian falls in these areas. Examining Aalborg specifically, it becomes evident that a significant number of accidents occur in the city centre, away from the major roads, explains Associate Professor Harry Lahrmann.

According to Harry Lahrmann, this is new knowledge. Traditionally, efforts to address accident blackspots have centred on major traffic routes. However, the inclusion of ambulance data in the new project reveals emerging blackspots, underscoring the need for Aalborg Municipality, among others, to address safety concerns on local roads as well.

More traffic accidents than initially assumed

The project processed data from the period 2016-19 within the borders of Aalborg Municipality. During this period, 963 personal injuries were reported from 765 unique traffic accidents by the police. In this project, the corresponding number was 3,358 personal injuries/ambulance calls distributed over a total of 2,466 unique traffic accidents including coordinates. Compared to police data, there are thus more than three times as many traffic accidents to work with when using ambulance data.

Dark figures are a problem

Dark figures in the area of traffic safety have been under scrutiny for some time. The fundamental problem in traffic safety work is that there is no comprehensive registration of all traffic accidents. Studies have shown that the official accident statistics based on police-registered accidents are burdened by a very large dark figure. The challenge in the so-called 'black spot work' in Denmark and other European countries is that the police do not necessarily attend many of the traffic accidents that occur on public roads. Therefore, there is no police report on all traffic cases, resulting in dark figures in the records.

More accurate traffic data in the future

Various stakeholders in traffic safety work have discussed whether other sources can be used to increase knowledge about traffic accidents. Data from ambulance calls is one of the possibilities that has now been successfully tested by the research group. The personnel in the emergency call centre, which receives the 112 calls, store information about the GPS coordinates to which the ambulance is dispatched. This makes it possible to collect this data and compare it with police records. Therefore, preventive work can in the future be based on more accurate data about the road sections where accidents actually occur.

- In this way, the work on traffic safety can be improved so that accidents can be better avoided in places that have not previously been registered as accident areas and therefore have not been the focus of preventive work," says Associate Professor Harry Lahrmann.