A CMS request for information does a good job of outlining the alternatives:
"Some argue it is necessary to attribute beneficiaries before the start of a performance period, so the ACO can target care coordination strategies to those beneficiaries whose cost and quality information will be used to assess the ACO's performance; others argue the attribution should occur at the end of the performance period to ensure the ACO is held accountable for care provided to beneficiaries who are aligned to it based upon services they receive from the ACO during the performance period. How should we balance these two points of view in developing the patient attribution models for the Medicare Shared Savings Program and ACO models tested by CMMI?"
The Disease Management Care Blog agrees with Drs. Feder and Cutler's answer. In the long term, the success of ACOs' will be the direct result of how well they reconcile the twin issues of protecting the rights as well as enabling the responsibilities of health consumers. If the ACO business model is ultimately based on "shared savings," it'll ultimately be the patient consumers who determine whether "bending the curve" was the result of good doctoring or unjust denials. Sooner or later, it'll be the patients - the ones who vote, write to members of Congress, call their State Attorney Generals and get interviewed by news organizations - who will need to buy-in to the merits of "high value" health care services.
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