No doubt there is interesting data to be mined here, but I wouldn't rely on it solely. The vast majority of patients are not in a good position to evaluate the quality of care they received. The kind of things they typically judge by are often fairly superficial attributes:

* did I have a long wait time?

* was the office staff polite and helpful?

* was my physician/NP/PA polite and helpful?

* were there billing problems after the appointment?

These things do matter, but there are more important factors in play that patients are not in a position to judge:

* were standards of care followed by the provider?

* were unnecessary tests ordered or unnecessary drugs proscribed?

* were necessary tests skipped or necessary drugs not proscribed?

* if they had access to my medical history, did the provider bother to review it before seeing me

* etc, etc.

Quality of care can absolutely be evaluated, and that's happening more and more, it's just that patient satisfaction is only one small part of the whole picture.