How experts look at accident scenes

Calling for help in the event of an accident – it is something that anyone may have to do. At an accident scene, what would you look for? And what would you say to the dispatcher who takes your call? Researchers at Linköping University have examined how novices and experts observe accident scenes.

An image of an accident with a tanker truck from an exercise for rescue services

A person who calls 112 is normally not a professional in emergency services, it is someone who happened to be present following an accident.

“In an emergency situation, it is often a novice, a layperson, who initiates the professional handling of the situation. For this reason we wanted to explore if there are differences in how novices and experts scan an accident scene with their gaze”, says Erik Prytz, research fellow at the Department of Computer and Information Science.

The study was conducted in conjunction with researchers at the Centre for Teaching and Research in Disaster Medicine and Traumatology. One group of subjects consisted of novices, the other of experts from emergency services and ambulance staff. They were shown images of an urban environment or an accident scene, and were asked to identify whether it actually was an accident. If it was, the subjects had one minute to describe the accident and the scene to a fictitious dispatcher. As they did this, eye-tracking equipment monitored their gaze.

“The images of the accidents contained what we call areas of interest – zones and objects in the image that are especially important in conveying information about the accident. These could be an injured person in the distance, or an information sign on a tanker truck that shows what is leaking from the tank”, explains Erik Prytz.

The results show that the experts spend more time observing these areas than the novices: they look at them for a longer time in total, and they fixate longer on the important areas each time they look at them.

Improved interview protocols

Since the novice is often the first link in dealing with the emergency, it is important that the information they provide to the experts is relevant. The dispatchers who take the calls have been trained in asking questions about the accident scene, and they follow various protocols to extract important information about what has happened.

The results of the study can improve the interviews and protocols, so when a novice speaks to the dispatcher they get help with focussing on relevant things at the accident scene. This way, the novice provides information that is useful in the prioritisation of resources. Also, the emergency services will be better prepared for what actually awaits them at the scene.

“In the future, emergency service call centres will be able to receive videos from the accident scene as well. In this scenario it is important to develop how dispatchers can guide novices at the scene, to get as much useful information as possible.”


Erik G. Prytz, Caroline Norén, Carl-Oscar Jonson: Fixation Differences in Visual Search of Accident Scenes by Novices and Expert Emergency Responders. First Published August 13, 2018. Human Factors.

Translation: Martin Mirko


The images of accident scenes were mainly from staged exercises for emergency services. The different-coloured tracks in the video show how the test subjects looked at the images. Orange represents novices, red is rescue services and blue is ambulance staff. The larger the circle, the longer the area in the image has been observed.



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