Mortality, fatality, and morbidity (proper use of terms)

The interesting article by Alden et al. in the July 1972 issue of Pediatrics is a too common example of the incorrect use of the word mortality where fatality is intended. Mortality represents the number of deaths per unit of population (100,000 now generally used and indicated) which population consists of the sick and the well, thus: mortality = deaths (for a given illness)/unit of population (100,000 sick and well) Fatality is based on the number of deaths per 100 cases of a given disease: