The mathematical relationship between the number of events in which people are injured and the number of people injured.

In this paper the mathematical relationship between the number of times people sustained injuries and the number of people injured is discussed. The number of injury-causing events in a population will be larger than the number of people injured as people can be injured on more than one occasion. The Poisson distribution is used as a way to study the relationship between the two different sets of numbers. A practical example is given of injuries sustained while running. From this it seems that injury proneness needs to be considered in studying those who were injured on more than one occasion while running during the past year.