That's the name of this New England Journal of Medicine article by Benjamin D. Sommers, Atul A. Gawande, and Katherine Baicker. They looked carefully at the literature asking whether having health insurance improves health outcomes. The authors also looked at a range of variables, including the quality of insurance. Here are excerpts from of their conclusions:
One question experts are commonly asked is how the ACA — or its repeal — will affect health and mortality. The body of evidence summarized here indicates that coverage expansions significantly increase patients’ access to care and use of preventive care, primary care, chronic illness treatment, medications, and surgery. These increases appear to produce significant, multifaceted, and nuanced benefits to health. Some benefits may manifest in earlier detection of disease, some in better medication adherence and management of chronic conditions, and some in the psychological well-being born of knowing one can afford care when one gets sick. Such modest but cumulative changes — which one of us has called “the heroism of incremental care”51 — may not occur for everyone and may not happen quickly. But the evidence suggests that they do occur, and that some of these changes will ultimately help tens of thousands of people live longer lives. Conversely, the data suggest that policies that reduce coverage will produce significant harms to health, particularly among people with lower incomes and chronic conditions. * * * There remain many unanswered questions about U.S. health insurance policy, including how to best structure coverage to maximize health and value and how much public spending we want to devote to subsidizing coverage for people who cannot afford it. But whether enrollees benefit from that coverage is not one of the unanswered questions. Insurance coverage increases access to care and improves a wide range of health outcomes. Arguing that health insurance coverage doesn’t improve health is simply inconsistent with the evidence.