The precise figure is unknowable because only 10% of such fraud is ever detected. Of course, health care organizations work tirelessly to thwart FWA. Pharmacy benefit managers (PBMs), which manage prescription drug benefits on behalf of health insurers by negotiating with drug manufacturers and pharmacies, are particularly adept at detecting FWA in drug dispensing, but typically lack visibility on the medical benefit side. "I could tell you all the drugs a patient received from a hospital, a retail pharmacy or a mail order pharmacy. But I couldn't show you the diagnosis attached to that claim," explains Jo-Ellen Abou Nader, Vice President of FWA and Supply Chain Optimization at Prime Therapeutics (Prime).