Rationale for the Development of a Traumatic Brain Injury Case Definition for the Pilot National Concussion Surveillance System.

Background: Current methods of traumatic brain injury (TBI) morbidity surveillance in the United States have primarily relied on hospital-based data sets. However, these methods undercount TBIs as they do not include TBIs seen in outpatient settings and those that are untreated and undiagnosed. A 2014 National Academy of Science Engineering and Medicine report recommended that the Centers for Disease Control and Prevention (CDC) establish and manage a national surveillance system to better describe the burden of sports- and recreation-related TBI, including concussion, among youth. Given the limitations of TBI surveillance in general, CDC took this recommendation as a call to action to formulate and implement a robust pilot National Concussion Surveillance System that could estimate the public health burden of concussion and TBI among Americans from all causes of brain injury. Because of the constraints of identifying TBI in clinical settings, an alternative surveillance approach is to collect TBI data via a self-report survey. Before such a survey was piloted, it was necessary for CDC to develop a case definition for self-reported TBI.

Objective: This article outlines the rationale and process the CDC used to develop a tiered case definition for self-reported TBI to be used for surveillance purposes.

Conclusion: A tiered TBI case definition is proposed with tiers based on the type of sign/symptom(s) reported the number of symptoms reported, and the timing of symptom onset.