Richard Kronick, a University of California San Diego medical professor who now works for the Department of Health and Human Services, wrote in 2009 that estimates are "almost certainly incorrect."
His paper, published in August 2009 in HSR: Health Services Research, found that uninsured participants had no different risk of dying than those were covered by employer-sponsored group insurance. The finding was surprising coming from Kronick, who told PolitiFact then it was "not the answer I wanted."
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Henry Aaron, a senior fellow at the centrist-to-liberal Brookings Institution, told us in an interview that he, too, thinks the number of deaths is impossible to nail down. In addition to Kronick’s skepticism, he pointed to a study of Oregon’s Medicaid experiment (which Baicker co-authored and PolitiFact looked at here) that found no significant improvement in health outcomes, including conditions like blood pressure, cholesterol and blood sugar, between a group of new Medicaid enrollees and uninsured Oregonians who could not get on the Medicaid rolls.
"Like Kronick, I am a strong advocate of measures to achieve universal insurance coverage and would rather that Kronick’s study and the Oregon project provided evidence in support of my policy preference," he said. "But, as far as mortality is concerned, they just don’t."