Abstract
OBJECTIVE: To compare characteristics of people with persisting post-concussion symptoms in a sample referred for treatment and in a sample from a prospective research study. DESIGN: Observational study. SUBJECTS: Participants, aged 18-60 years, with persisting post-concussion symptoms 3-18 months after mild head injury, 92 with mild traumatic brain injury followed from the emergency department ("prospective emergency department sample") and 106 patients with either mild traumatic brain injury or minimal head injury, referred to an outpatient rehabilitation clinic ("clinical rehabilitation sample"). METHODS: Persisting post-concussion symptoms were defined as having British Columbia Post-Concussion Symptom Inventory scores indicating at least moderate persisting post-concussion symptoms and/or Rivermead Post Concussion Symptoms Questionnaire (RPQ) scores ≥ 12. Symptoms, functional outcome, work/school participation, resilience, and fatigue were examined at 3-18 months post injury. RESULTS: Compared with the prospective emergency department sample, the clinical rehabilitation sample had higher education, higher RPQ scores (30 vs 17), lower Glasgow Outcome Scale Extended scores (median 6 vs 7), and more had not returned to work or school (43% vs 18%). CONCLUSION: Treatment-seeking patients with persisting post-concussion symptoms differed in clinically important ways from people who developed persisting post-concussion symptoms in an emergency department-based mild traumatic brain injury study. Results from studies of mild traumatic brain injury seen in the emergency department may not generalize to patients seeking specialized treatment for persisting post-concussion symptoms.