In this study, self-reported symptoms (cognitive, physical, behavioural/affective) from the TIRR Symptom Checklist are compared across six panels: 135 individuals with mild TBI, 275 with moderate/severe TBI, 287 with no disability, 104 with spinal cord injury, 197 who are HIV positive and 107 who had undergone liver transplantation. Participants with TBI and SCI were at least 1 year post-injury. Individuals with TBI reported significantly more symptoms than other panels. Symptom reports in the TBI panels were independent of demographic variables (gender, education, income, ethnicity, age), as well as time since injury and depression. Five of the 67 symptoms were found to be sensitive/specific to TBI in general; 25 symptoms were sensitive/specific to mild TBI (23 were cognitive, one physical and one behavioural/affective). Implications of these results in terms of current debates about the 'reality' of symptom reports in individuals with mild TBI are discussed, as well as implications for using symptom checklists for TBI screening.