Missed Diagnoses in Rural Mild TBI: The Role of EMS Delays

Background Mild traumatic brain injury (mTBI) diagnosis relies on observing acute neurological signs including loss of consciousness, post-traumatic amnesia, confusion and transient motor signs. Current guidelines assume real-time observation, creating systematic underdiagnosis when emergency medical services (EMS) arrival exceeds transient qualifying sign duration—particularly problematic in rural systems with transport delays. Objective To model the missed-diagnosis window — the probability that qualifying signs resolve before first medical contact. Methods We synthesized published EMS response distributions, acute neurological sign durations, and consensus guideline criteria to model the missed-diagnosis window—the probability that qualifying signs resolve before first medical contact. Analysis incorporated systematic review evidence from 37 studies (n=239,464,121 patients). Results Critical neurological signs resolve rapidly: median loss of consciousness <1 minute, altered mental status ~5 minutes, brief post-traumatic amnesia <30 minutes. EMS arrival approximates 15 minutes (urban) versus 25 minutes (rural). This temporal mismatch produces P (missed diagnosis) >0.70 in rural systems when arrival exceeds 20 minutes—representing systematic 70% underdiagnosis where guidelines default to “sign absent” rather than “sign unobserved.” Conclusions Implementing time-sensitive, retrospective, and telehealth-supported pathways within existing EMS protocols is both feasible and defensible, reducing missed diagnoses of mild traumatic brain injury in rural settings. By addressing EMS delays directly, this approach strengthens diagnostic accuracy, advances equity in rural health, and moves toward a new standard of care in emergency medicine.