I'm a medical user myself using it to treat ulcerative colitis. I use a 5mg dose of tincture twice daily. I don't need to have a double blind study to tell me it works since I no longer have to suffer from constant cramps or spend 4 hrs a day on the toilet. Also helps out nicely with my arthritis. I no longer have to take NSAIDs which aggravated my condition. And the dose is low enough it never makes me feel high. I haven't actually smoked it in years but I do like to vaporize it before going on my 20 mile bike loop. Other than that, I don't really enjoy getting high.
Currently NIDA controls all the research done on cannabis, but they won't allow any to be done unless the study is commited to proving a negative. It was considered a very effective medicine for thousands of years before our government arbitrarily decided to make it a crime.