When the study kicked off, 14 percent of these tests included an anesthesiologist. That climbed to more than 30 percent by 2009. The portion of this extra sedation treatment given to low-risk commercially insured patients remained constant during the study and fell slightly in Medicare fee-for-service patients. But the study authors said far too many low-risk patients are still getting this treatment - more than three-fourths of the commercially insured patients and two-thirds of the Medicare group.