This number has been calling my cell and my house almost daily for several months. They never leave a message, so I can't confirm this with 100% accuracy, but I think it's none other than Central Kentucky Management Services, the bill collectors for the University of Kentucky Hospital, also known as Kentucky Medical Services Foundation, or KMSF.
If someone has the ability to run a hard back trace (one of the paid traces) on this number and confirm this, it would be greatly appreciated.