The Life Events Checklist for DSM‐5 (LEC‐5) is a comprehensive screening instrument used to detect exposure to a range of potentially traumatic events. Despite its widespread use, research assessing the psychometric properties of scores on the LEC‐5—and trauma exposure more broadly—is scarce. Using a large sample of undergraduate students (N = 1,013), we sought to evaluate the reliability of trauma exposure reporting on the LEC‐5 across 8‐ (N = 379) and 12‐week (N = 343) intervals. Reliability estimates were examined for trauma exposure type (e.g., experiencing, witnessing), traumatic event type (e.g., sexual assault), and index trauma (i.e., “worst event”) reporting. Reliability was more stable for events that were directly experienced, intraclass correlation coefficients (ICCs) = .62–64, than events that were witnessed, ICCs = .47–.52, or learned about, ICCs = .48–.53. Test–retest agreement was fair to good for reports of sexual assault, physical assault, transportation accidents, natural disasters, and other sexual experiences, κs = .49–.72, but only when individuals directly experienced these events. By contrast, across both assessment intervals, the agreement was attenuated, all κs < .40, for events that individuals witnessed or learned about regardless of event type. For index events, only sexual assault and sudden accidental or violent deaths were consistently reported with a fair or better agreement, κs = .42–.64. These findings suggest that reliable trauma reporting varies largely based on the nature of the traumatic event, yielding important implications for the assessment of DSM‐5 Criterion A and posttraumatic stress disorder.
