Traumatic Brain Injury Trends Altered by Case Definition Selection, Study Finds

Strategic Insights -

A recent study by researchers at the University of North Carolina Gillings School of Global Public Health has found that the selection of case definition for traumatic brain injury (TBI) significantly impacts statewide trends. The study, which analyzed emergency department visit records from 2012 to 2024, discovered that the inclusion of unspecified head injuries in the TBI surveillance case definition substantially altered statewide trends and may better reflect injury burden. The research, published in the Annals of Epidemiology, highlights the importance of careful case definition selection in accurately quantifying TBI incidence.

Key Takeaways:

  • The CDC's removal of unspecified head injuries from its TBI surveillance case definition in 2015 complicated the investigation of long-term morbidity trends.
  • The study examined the long-term impact of this change on quantifying statewide TBI incidence using segmented Poisson regression.
  • From January 2012 through September 2015, TBI visits increased at a rate of 14.9 visits per month.
  • TBI visits dropped at the onset of COVID-19, and then rebounded after the relaxation of the state's stay-at-home-order, but this trend was diminished under the S09.90- definition.
  • The difference in TBI visit counts between the two definitions was significant, with a difference of 75.9 (57.2-94.6) visits per month.
  • The study concludes that the inclusion of unspecified head injuries in the TBI surveillance case definition may better reflect injury burden.

Statistics:

  • TBI visits increased at a rate of 14.9 visits per month from January 2012 through September 2015.
  • TBI visits dropped by an average of 75.9 (57.2-94.6) visits per month at the onset of COVID-19.
  • The state's stay-at-home-order received a 25% boost in the number of newly diagnosed cases.

Sources:

  • Implications of case definition selection on traumatic brain injury trends: A controlled interrupted time-series analysis of North Carolina emergency department data. Annals of Epidemiology, 2025;111:82-86.
  • NewsRx. Researchers from University of North Carolina Gillings School of Global Public Health Detail New Studies and Findings in the Area of Traumatic Brain Injury (Implications of case definition selection on traumatic brain injury trends: A ...). Pain & Central Nervous System Week. October 13, 2025; p 763.