Missouri has approved thousands more people to use marijuana as medicine within the first six months of the process than researchers in a state-commissioned study predicted the state would see by the end of 2020, and that number could continue to outpace predictions through 2022, advocates say. 

Marijuana advocates said in April that the study — which used data from 2015 culled from 19 states — underestimated the number of patients Missouri would see because it used old data from states with widely varying medical marijuana programs. 

Missouri could have at least 122,000 medical marijuana patients by the end of 2022, said Missouri Medical Cannabis Trade Association spokesman Jack Cardetti.  The number is based on a trend in states like Colorado that saw 2% to 3% of the state population licensed as marijuana patients after approving medical use, he said. 

In the university study, researchers averaged numbers from 19 states that have legalized medical marijuana, looking chiefly at Washington, Arizona, Massachusetts and Colorado, which they said offered the most complete data available. The 46-page study projected the supply of marijuana would outpace demand and that the market would not support the number of businesses the state planned to license. 

But because of the differences in state programs and how thoroughly they kept track of data, the study was only able to make projections “with 66% confidence” of how much marijuana patients would need.

At the most, Missouri could have 69,272 qualified medical marijuana patients by 2022, according to the study. But even that number of patients, the study said, wouldn’t generate enough demand for the first three years for 60 commercial marijuana growers.

The law provided for as many marijuana businesses because it ensured greater access for patients and would generate competition in the market, Cardetti said. 

“We think that’s good for patients and we think that’s good for the industry,” he said.