Table 1.
Studies related to the legalization of medical cannabis: country, sample, and most relevant variables.
| Article | Country (States)/Years | Sample Size | Study Group | Variables | Data Collected/Detection Method |
|---|---|---|---|---|---|
| Jones et al. (2019) [22] | U.S. (Arizona) (2008–2014) | THC+: N = 2590 Alcohol+: N = 5266 THC+ and alcohol: N = 1086 |
Injured driver | Use of cannabis, alcohol, or both substances after a traffic accident. Pre-legalization: January 2008–April 2011; Post-legalization: April 2011–December 2014. | Urine drug screens for cannabis metabolites and BAC. |
| Wadsworth and Hammond (2019) [23] | Canada, England, and U.S. July, 2017 | Canada: N = 4008 England: N = 3970 U.S.: N = 4086 |
Youth | Use, access, perceptions of harm and driving after cannabis and/or alcohol use. Sociodemographic variables. | Self-report completed using web-based surveys. |
| Steinemann et al. (2018) [24] | U.S. (Hawaii) (1993–2015) | Pre-legalization (1993–2000): N = 560; THC+ 31 (6%). Post-legalization (2001–2015): N = 1018. THC+ 151(15%). |
Drivers killed | THC+ and alcohol in drivers. Pre- and post-legalization. | FARS. Urine toxicology and blood drug test. |
| Sevigny (2018) [25] | U.S. (1993–2014) | Nearly 1.2 million drivers involved in fatal traffic accidents. THC+ 8.8% BAC ≥ 0.08 = 20.1%. |
Drivers | Presence of THC, other illicit drugs, and alcohol. Variables related to cannabis regularization. Contextual and control variables. |
FARS. Blood drug test. |
| Santaella-Tenorio et al. (2017) [26] | U.S. (50 states) (1985–2014) | N = 1,220,610. | Deaths in traffic accidents | Fatal traffic accidents. Age 14–24, 25–44, and 45< years. Date MML by State. Dispensaries. |
FARS. Blood drug test. |
| Masten and Guenzburger (2014) [27] | U.S. (14 states that have legalized cannabis and 37 jurisdictions without MCL) (1992–2009) | Drivers involved in fatal crashes: THC+ N = 19,977. |
Drivers | Presence of THC in drivers involved in fatal traffic accidents. | FARS. Blood and/or urine drug test. |
| Salomonsen-Sautel et al. (2014) [28] | U.S. (Colorado and 34 states without MCL) (1994–2011) | Proportions of drivers involved in fatal crashes. Colorado: THC+ between 4.5% to 10%. States without MCL: THC+ between 1.1% to 4.1% | Drivers | THC+ or alcohol BAC ≥ 0.08. Pre-commercialization, June 1994–July 2009; Post-commercialization, July 2009–2011. |
FARS. Blood and/or urine drug test. |
| Anderson et al. (2013) [29] | U.S. (1990–2010) | Age: 15–60< years old. 20.48 (7.15) |
Fatalities per 100,000 people | Fatal traffic accidents. Sociodemographic variables. Control states and MCL states. |
FARS. Blood drug test. |
Note: BAC (blood alcohol concentration), FARS (Fatality Analysis Reporting System database), and MCL (medical cannabis legalization).