Examination of the Role of the Combination of Alcohol and Cannabis in South Australian Road Crashes

Abstract

The findings of the hospital data and the coroners' reports were consistent with each other in terms of providing confirmation that alcohol is still the drug associated with the greatest level of road trauma on South Australian roads. Furthermore, alcohol was also present in around half of the cannabis cases and, when present, tended to be present at very high levels. The results of this study emphasize that, although drug driving is clearly a problem, the most important form of impaired driving that needs to be the target of enforcement is drink driving. Roadside drug testing is important but should not be conducted in such a way that reduces the deterrent value of random breath testing.

Effects of 3,4‐methylenedioxymethamphetamine and methamphetamine on motor vehicle driving performance: A systematic review of experimental and observational studies

“…The results below highlight the prevalence of driving under the influence of drugs (DUID), legal charges, MVAs, FVAs, impairment analyses, road rage occurrence, and driver's perception of DUI or legal risk when under the influence of METH or MDMA. The 35 descriptive case series [11, 12, 41–73], provide supplemental information regarding cases that were involved in MVAs, SDUID or a similar violation, or charged with DUID or a similar violation. METH or MDMA exposure was determined mainly by subject interview and/or blood, urine, and oral fluid analysis.…”

“…Another limitation of observational studies includes challenges performing risk ratios of single substances (e.g., MDMA or METH), when subjects were positive for multiple substances in DUI, MVA, or FVA cases. Due to these limitations and few case‐control, case‐cohort, and studies with a similar design, we included 35 case series articles in effort to review more observational data [11, 12, 41–73]. Case series are generally accepted as having lower scientific rigor, and therefore, less emphasis was placed on them in the results.…”

“…Nine experimental studies were included which assessed METH ( n = 4) [5, 8, 25, 26] or MDMA ( n = 5) [4, 27–30] under simulated or actual driving conditions. Forty‐five articles were observational studies, which included cross‐sectional studies ( n = 2) [31, 32], case‐control studies ( n = 2) [33, 34], a case‐crossover study [35], a culpability analysis [36], a logistic regression analysis [37], a cohort study [38], structured interviews ( n = 2) [39, 40], and descriptive case series ( n = 35) [11, 12, 41–73].…”

“…Nine studies reported exposure in FVAs, with prevalence ranging from 0.3% to 7.1% [42,45,46,48,51,54,57,66,69], with a reported mean blood METH concentration to be 73 ng/ml [66] and a blood concentration range of 17-210 ng/ml [45,46]. Two studies reported exposure to methamphetamine in MVAs, with prevalence ranging from 1.9% to 9.7% [42,60]. Wiese Simonsen et al [72] reported METH exposure in 1.5% of MVAs who required hospitalization, where mean blood METH concentration ranged from 2.2 to 228 ng/ml.…”

Alcohol and marijuana use among young injured drivers in Arizona, 2008–2014

“…A separate survey reported that among persons aged 18-29 years who drink alcohol, 15% report some simultaneous use of alcohol and marijuana (Subbaraman and Kerr 2015). The authors further use among injured drivers of all ages consistently find alcohol and marijuana to be among the most commonly detected substances, and the 2 are often found in combination (Baldock and Lindsay 2015;Brubacher et al 2016;Walsh et al 2005).…”