The purpose of this paper is to describe the methods used to analyze 6000 individual road accidents observed in a definitive area by the same medical team.

It examines the circumstances of the accident, the injuries observed, their treatment, evolution, and final results with their sociological and economical consequences.

This study attempts to establish the relationship between the signs of severity recorded on the spot and the real final evaluation. It insists upon the primary importance of lesion associations, leading to two major groups of victims:​ the polyinjured whose injuries add themselves up without getting worse, and the polytraumatic victims (the real experimental result of the lesions on a body in motion) whose injuries are latent and get worse mutually.

The 6000 observations constitute many months of work. This preliminary study deals with 800 cases and attempts to point out the methodology rather than the results.