The epidemiology of head injury: a prospective study of an entire community-San Diego County, California, 1978.

In 1978, a prospective study of all deaths from head injury and of all patients admitted to hospitals with a diagnosis of head injury was conducted in San Diego County, California. The overall incidence of head injury was nearly 0.3%; the highest rate was seen at ages 10-29 years. At all ages, head injury rates were higher in males than in females, and the death rate in males was 2.6 times that in females. The overall case fatality ratio was 7.5%, and 65% of all deaths occurred prior to hospitalization. Among those who survived to hospitalization, the case fatality ratio was less than 3%. Motor vehicle accidents caused 53% of all head injuries and 73% of all deaths. Although other causes of head injury showed seasonal variation, the frequency of motor vehicle head injuries did not vary by month.