TY  - JOUR
PY  - 2017//
TI  - Interaction of marijuana and alcohol on fatal motor vehicle crash risk: a case-control study
JO  - Injury epidemiology
A1  - Chihuri, Stanford
A1  - Li, Guohua
A1  - Chen, Qixuan
SP  - e8
EP  - e8
VL  - 4
IS  - 1
N2  - BACKGROUND: Concurrent use of marijuana and alcohol in drivers is of increasing concern but its role in crash causation has not been well understood. <br><br>METHODS: Using a case-control design, we assessed the individual and joint effects of marijuana and alcohol use on fatal crash risk. Cases (n = 1944) were drivers fatally injured in motor vehicle crashes in the United States at specific times in 2006, 2007 and 2008. Controls (n = 7719) were drivers who participated in the 2007 National Roadside Survey of Alcohol and Drug Use by Drivers. <br><br>RESULTS: Overall, cases were significantly more likely than controls to test positive for marijuana (12.2% vs. 5.9%, p < 0.0001), alcohol (57.8% vs. 7.7%, p < 0.0001) and both marijuana and alcohol (8.9% vs. 0.8%, p < 0.0001). Compared to drivers testing negative for alcohol and marijuana, the adjusted odds ratios of fatal crash involvement were 16.33 [95% confidence interval (CI): 14.23, 18.75] for those testing positive for alcohol and negative for marijuana, 1.54 (95% CI: 1.16, 2.03) for those testing positive for marijuana and negative for alcohol, and 25.09 (95% CI: 17.97, 35.03) for those testing positive for both alcohol and marijuana. <br><br>CONCLUSIONS: Alcohol use and marijuana use are each associated with significantly increased risks of fatal crash involvement. When alcohol and marijuana are used together, there exists a positive synergistic effect on fatal crash risk on the additive scale.    Keywords: Cannabis impaired driving, alcohol impaired driving<p />  <p>Language: en</p>
LA  - en
SN  - 2197-1714
UR  - http://dx.doi.org/10.1186/s40621-017-0105-z
ID  - ref1
ER  -