While some public hospitals do well on measures of patient care, many get lower ratings because of the added challenges they face, such as caring for more uninsured people, said Bruce Boissonnault, CEO of the Niagara Health Quality Coalition. Starting in October, hospital payments for Medicare patients will undergo a historic change. Using Hospital Compare scores, Medicare, the largest single payer of hospital services, will reward hospitals based on the quality of care they provide, not just on the quantity of services they deliver. Many states, including Texas, are overhauling their Medicaid programs for the poor in a similar way.