A community survey demonstrated cohort differences in the lifetime prevalance of self- reportrd head injury

Objective The objective of the study was to assess the lifetime prevalence and validity of self-reported head injury. Study design and setting Analysis of a cross-sectional community survey, stratified by birth cohort. Seven thousand four hundred eighty-eight residents of Canberra and Queanbeyan, 3,678 males and 3,810 females, representing three cohorts aged in their 20s, 40s and 60s at the time of the survey, were randomly selected from the Australian Electoral Roll. Results The lifetime prevalence of head injury with at least 15 min loss of consciousness ranged from 5.6 to 6.0% across the three cohorts. Self-reported head injury was associated with symptoms of traumatic brain injury or postconcussion syndrome. Reported head injury did not differ across the birth cohorts, contrary to expectations that prevalence rates would increase with age. Analysis of age at first head injury showed significant differences between cohorts in the reported prevalence at age 20, with estimates considerably higher for the youngest cohort. Conclusion Although the data may reflect real increases in the risk of head injury, it may be that self-reported measures of lifetime prevalence of head injury underestimate prevalence in older cohorts