Limit diagnoses that can use medical marijuana to those diagnoses which have been proven in clinical trials to benefit from the drug.
Limit diagnoses for which doctors can prescribe medical marijuana to those that have clinical research backing the use of the medication. This is the standard that other drugs must provide, and it is the standard that doctors are held accountable to under their malpractice insurance. If this is truly a "medical" drug, then treat it like any other medical drug, and wait for the data to support it's use and prove its safety and effectiveness. Research should be of the same standard expected of drug companies.
Thank you for bringing up the importance of scientific evidence. We are bound to accept applications for all the conditions that were approved by voters, but Director Will Humble has been very clear about adding new conditions. He posted a series of entries on his blog discussing it:
Kyle Catlin commented
Research has already been done it is safe and effective. have you done any research? its the safest medicine on earth!