Marijuana self-report compared with testing in trauma patients before and after legalization.

Background: Both marijuana use and legalization are increasing, and the cognitive effects of marijuana may play a role in trauma. Our objective was to assess the proportion of patients with a urine drug screen who self-reported use in a population of trauma patients. Methods: Self-report of marijuana use in trauma patients was recorded for patients with a positive urine toxicology screen at a Level 1 trauma center in Arizona prior to (1/2011 to 4/13/2011) and following (4/14/2011 to 9/2014) legalization of marijuana for medical indications. Results: Among patients with a positive toxicology screen who were able to report to utilization, 52.5% patients with a positive UDS for marijuana overall reported use. In the pre-legalization group, 59.3% reported use, while in the post-legalization group, 51.4% reported use (p=.188). Conclusion: Only about half of trauma patients with a positive urine drug screen for marijuana reported use. Self-reporting among UDS-positive patients demonstrated no significant change with the legalization of marijuana for medical reasons.