Expert Panel Survey to Update the American Congress of Rehabilitation Medicine Definition of Mild Traumatic Brain Injury.

Abstract Objective As part of an initiative led by the Brain Injury Special Interest Group Mild Traumatic Brain Injury (TBI) Task Force of the American Congress of Rehabilitation Medicine (ACRM) to update the 1993 ACRM definition of mild TBI, the present study aimed to characterize current expert opinion on diagnostic considerations. Design Cross-sectional web-based survey Setting Not applicable. Participants An international, interdisciplinary group of clinician-scientists with expertise in mild TBI completed the survey by invitation between May and July 2019 (N=31, 100% completion rate). Intervention(s) None. Main Outcome Measures Ratings of agreement with statements related to the diagnosis of mild TBI and ratings of the importance of various clinical signs, symptoms, test findings, and contextual factors for increasing the likelihood that the person sustained a mild TBI, on a scale ranging from 1 (“Not at all important”) to 10 (“Extremely Important”). Results Males (n=25; 81%) and Americans (n=21; 68%) were over-represented in the sample. The survey revealed areas of expert agreement (e.g., acute symptoms are diagnostically useful) and disagreement (e.g., whether mild TBI with abnormal structural neuroimaging should be considered the same diagnostic entity as “concussion.”). Observable signs were generally rated as more diagnostically important than subjective symptoms (Wilcoxon signed ranks test Z=3.77, p > 75% of respondents indicated at least 7 out of 10). Conclusions The expert survey findings identified several potential revisions to consider when updating the ACRM mild TBI definition, such as preferentially weighing observable signs in a probabilistic framework, incorporating symptoms and test findings, and adding differential diagnosis considerations.