The current study examined the role of factors identified by the World Health Organization's Task Force on Mild Traumatic Brain Injury as being associated with poor outcome after mild traumatic brain injury. Employing symptom severity ratings at 3 months post-injury greater than "mild," subgroups of Higher-Severity (20%) and Lower-Severity (80%) participants were identified. Findings revealed that individuals who report greater symptom complaints at 3 months post-MTBI may be identifiable soon after injury on the basis of the magnitude and severity of early self-reported symptoms, pre-morbid psychological issues, and involvement in compensation-seeking. Injury severity factors did not differ between the groups.