Steven Lewis is right that as people learn the system they will try and game it. What about perverse incentives of the fee for service or piecework that reward turnstile medicine. Physicians that try and put in a lot of effort on frail elderly patients with multiple chronic conditions are subsidizing the fee for service system. About 14 years ago BC started a population based payment system that has a payment formula that has a lot of check and balances built in so that it would be difficult to game the system in a bad way. There are built-in incentives for comprehensive care, chronic disease management and patient involvement. The only ways of gaming this system will push the physicians into providing better care.