John Kasich and other governors are weighing whether to expand Medicaid. In doing so, they would do well to examine a new study from the School of Public Health at Harvard. Researchers reported last week via the New England Journal of Medicine that giving more poor people health insurance results in fewer deaths.

Such an assessment long has been tricky, tracking the health outcomes of those in Medicaid against those who are eligible yet remain uninsured. The Harvard group makes a credible try at charting the difference. It looked at the mortality rates in three states that expanded Medicaid coverage compared to four neighboring states that did not. After adjusting for a range of factors, the study concluded that the Medicaid expansions yielded a 6 percent decline in deaths.

No question, the study has imperfections. It looked at overall deaths, not just those in the Medicaid population. Yet it is noteworthy that the sharpest decline in deaths was among nonwhites and people living in poorer counties. More, the study echoes work in Oregon, where a Medicaid expansion led to recipients seeing the doctor more often, achieving improved health results and greater financial stability.

A Medicaid expansion presents hard choices for states, especially for those struggling with persistent budget deficits. What they must resist is fixing narrowly on the increase costs. There are real benefits to expanding coverage in elevating the quality of lives. When Gov. Kasich set out to revamp Medicaid in pursuit of savings, he said no to shrinking coverage. That is the right instinct.