By Guy Bentley
Getting behind the wheel while stoned is indeed dangerous but not nearly as much as previously thought, according to a study by two Norwegian researchers.
Published in the journal Addiction, the study investigated how likely drivers who had been using cannabis were to get into a car accident. The researchers looked at 20 studies and two meta-analyses published between 1982 and 2015.
The study reportedly has a more unusual conclusion than previous research because it corrected for perceived methodological flaws of past studies. These methodological inaccuracies mean previous studies overestimated the risk of marijuana use while driving, according to the paper.
“Higher estimates from earlier meta-reviews were found to be largely driven by methodological issue,” said the authors. “In particular the use of data without adjustment for known confounders,” which include gender and age.
Correcting for these factors altered the results, giving a lower-risk profile. “Acute cannabis intoxication is related to a statistically significant risk increase of low to moderate magnitude [odds ratio between 1.2 and 1.4],” the study said.
These figures compare very favorably to alcohol, according a 2015 study by the U.S. National Highway Traffic Safety Administration. The study found that those driving with the legal amount of booze in their systems have an almost four-fold increased risk of crashing.