OBJECTIVE To provide item analyses, estimates of temporal reliability and internal consistency, and examination of the sensitivity and specificity of a traumatic brain injury-screening tool. PARTICIPANTS Five hundred veterans of the wars in Iraq and Afghanistan enrolled in the study, approximately half of whom (248) volunteered. The remaining 252 participants were referred to Veteran Affairs (VA) neuropsychology or polytrauma clinics. DESIGN This psychometric study constitutes part of a larger 4-year, multisite prospective cohort study of veterans returning from Iraq and Afghanistan. SETTING Five VA medical centers and one VA outpatient clinic. MAIN MEASURES Veteran traumatic brain injury screening tool (VATBIST), a structured diagnostic interview for traumatic brain injury; a military-oriented posttraumatic stress disorder checklist. RESULTS The VATBIST appeared to have high-internal consistency (0.77) and test-retest reliability (0.80), high sensitivity (0.94) and moderate specificity (0.59). Diagnostic odds ratios for the screening tool ranged from 12.6 for the total sample to 24, when veterans with probable posttraumatic stress disorder were excluded from analysis. CONCLUSIONS The VATBIST appears to be a reliable and valid instrument. The presence of significant posttraumatic stress disorder symptoms, however, reduces the accuracy of the measure and highlights the need for careful clinical follow-up of persons who screen positive.