Since most ACOs are local, who would be the most important partners in an ACO who would have the type of data needed to plan for services?

ACOs are a model whose purpose is to determine a population's current health care needs based upon diagnostic and treatment services provided, environment of care, frequency of use and clinical provider type.  Since most ACOs are local, who would be the most important partners in an ACO who would have the type of data needed to plan for services?

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