Consistency of traumatic brain injury reporting in older adults with and without cognitive impairment

Objective: Medical history information regarding prior traumatic brain injury (TBI) usually relies on self-report, although little is known about the reliability of this information with regard to injuries sustained years or decades earlier. Even less is known about the reliability of self-reported medical history information in older individuals with cognitive impairment. To this end, we assessed the test-retest reliability of self-reported TBI history in a large, national sample. Methods: Participants (n=4309) were older adults with intact cognition, mild cognitive impairment (MCI) and Alzheimer's disease (AD) from the National Alzheimer's Coordinating Center. Subjects provided TBI history information at baseline and one annual follow-up visit. Consistency of self-reported history of TBI with<5minutes loss of consciousness (mLOC) and TBI with5 mLOC reported at time 1 and 2 was analyzed across diagnostic groups. Results: Overall, subjects provided reports of TBI history at follow-up that were highly consistent with baseline reports (97.8-99.6% agreement), and Cohen's kappa coefficients were all larger than .80 and statistically significant, maximum p<.001. Furthermore, level of cognitive impairment was not a significant predictor of consistency in reporting. Conclusions: These data are some of the first to suggest that self-report may be a consistent method of obtaining remote TBI history in the absence of medical records for older individuals, regardless of cognitive impairment.