A study published in September in JAMA Network Open, a peer-reviewed publication under the American Medical Association umbrella, found “little evidence” that adult and medical use cannabis legalization “encourage youth marijuana use.” It was a compelling study, and Cannabis Wire interviewed the lead author by email for our coverage. On Tuesday, the journal published a “Notice of Retraction and Replacement.” Methodological concerns raised by researchers prompted a new data analysis, which made the declines in youth use no longer “statistically significant.” “We apologize to the readers and editors of JAMA Network Open for any confusion we caused,” the authors wrote in the notice. So what happened? Importantly, the authors of the original study used “unweighted and pooled national and state” data from the Youth Risk Behavior Survey for the time frame 1993 to 2019, a time period when states overhauled their cannabis laws, starting with California in 1996. It was this “pooling” of data that was the problem. “While this unweighted and pooled approach maximized the number of state policy changes used to identify the effect of marijuana legalization on youth marijuana use for the average student in the pooled sample, published Comments advised that the approach was inappropriate,” authors Mark Anderson and Joseph Sabia wrote in a letter published Tuesday. One of the researchers who wrote a comment of concern was Nora Volkow, director of the National Institute on Drug Abuse.
Alyson Martin, Cannabis Wire, 03/08/2022 19:00:00