Seattle, WA: Adults who consume cannabis are most likely to smoke it, according to data compiled by the US Centers for Disease Control (CDC) and published in the journal Drug and Alcohol Dependence.
Researchers analyzed data from over 6,100 adult cannabis consumers in twelve states. Ninety-one percent of respondents acknowledging having smoked herbal cannabis, with 59 percent reporting that inhalation "was their only mode of marijuana use." By contrast, only 25 percent of respondents reported having ever used cannabis-infused edible products, and only 20 percent reported ever having vaporized cannabis. Five percent of subjects reported exclusively consuming marijuana edibles, and two percent said that they only vaped cannabis.
The data is consistent with prior studies, such as those here and here, showing that the majority of people who self-report consuming cannabis do so by methods that involve smoking the substance.
Full text of the study, "Modes or marijuana use: Smoking, vaping, eating, and dabbing – Results from the 2016 BRFSS in 12 states," appears in Drug and Alcohol Dependence.