CHICAGO (AP) — A hearing in Chicago will deal with the tricky question of whether scientific evidence supports military veterans with post-traumatic stress disorder using marijuana to manage their symptoms.

Monday’s hearing is a step toward expanding the Illinois medical marijuana program to include PTSD and other conditions.

An advisory board made up of patients, nurses, doctors and a pharmacist will hear testimony. The board will make recommendations to the Illinois Department of Public Health.

Supporters of marijuana research say federal obstacles make it difficult to provide solid evidence. They include Dr. Sue Sisley, an Arizona investigator pursuing a study that’s on track to be the most rigorous trial so far of marijuana for veterans with PTSD.

Sisley has come to Chicago and has requested a meeting with the Department of Public Health.

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