Sarah Taubman

Medicaid Increases Emergency-Department Use: Evidence from Oregon's Health Insurance Experiment

Health Economy? The intensity of arguments over social science issues often seems inversely correlated with the quantity of experimental evidence. Taubman et al. (p. 263, published online 2 January; see the Policy Forum by Fisman) report on the latest analysis of an ongoing controlled experiment—the Oregon Health Insurance Experiment—that seeks to identify and quantify the effects of extending health insurance coverage to a low-income adult population. A substantial increase was observed in visits to the emergency departments of hospitals, corresponding to approximately 120 U.S. dollars per year more in hospital costs. Expanding health coverage of low-income adults can result in increased usage of hospital emergency departments. In 2008, Oregon initiated a limited expansion of a Medicaid program for uninsured, low-income adults, drawing names from a waiting list by lottery. This lottery created a rare opportunity to study the effects of Medicaid coverage by using a randomized controlled design. By using the randomization provided by the lottery and emergency-department records from Portland-area hospitals, we studied the emergency department use of about 25,000 lottery participants over about 18 months after the lottery. We found that Medicaid coverage significantly increases overall emergency use by 0.41 visits per person, or 40% relative to an average of 1.02 visits per person in the control group. We found increases in emergency-department visits across a broad range of types of visits, conditions, and subgroups, including increases in visits for conditions that may be most readily treatable in primary care settings.

The Oregon Health Insurance Experiment: When Limited Policy Resources Provide Research Opportunities

In 2008 Oregon allocated access to its Medicaid expansion program, Oregon Health Plan Standard, by drawing names from a waiting list by lottery. The lottery was chosen by policy makers and stakeholders as the preferred way to allocate limited resources. At the same time, it also gave rise to the Oregon Health Insurance Experiment: an unprecedented opportunity to do a randomized evaluation - the gold standard in medical and scientific research - of the impact of expanding Medicaid. In this article we provide historical context for Oregons decision to conduct a lottery, discuss the importance of randomized controlled designs for policy evaluation, and describe some of the practical challenges in successfully capitalizing on the research opportunity presented by the Oregon lottery through public-academic partnerships. Since policy makers will always face tough choices about how to distribute scarce resources, we urge thoughtful consideration of the opportunities to incorporate randomization that can substantially improve the evidence available to inform policy decisions without compromising policy goals.

Randomize evaluations to improve health care delivery

Administrative data and experimental designs lead the way The medical profession has long recognized the importance of randomized evaluations; such designs are commonly used to evaluate the safety and efficacy of medical innovations such as drugs and devices. Unfortunately, innovations in how health care is delivered (e.g., health insurance structures, interventions to encourage the use of appropriate care, and care coordination approaches) are rarely evaluated using randomization. We consider barriers to conducting randomized trials in this setting and suggest ways for overcoming them. Randomized evaluations of fundamental issues in health care policy and delivery should be—and can be—closer to the norm than the exception.

The Effect of Medicaid on Management of Depression: Evidence From the Oregon Health Insurance Experiment

Policy Points: We take advantage of Oregons Medicaid lottery to gauge the causal effects of Medicaid coverage on mental health care, how effectively it addresses unmet needs, and how those effects differ for those with and without a history of depression. Medicaid coverage reduced the prevalence of undiagnosed depression by almost 50% and untreated depression by more than 60%. It increased use of medications and reduced the share of respondents reporting unmet mental health care needs by almost 40%. There are likely to be substantial mental health consequences of policy decisions about Medicaid coverage for vulnerable populations. CONTEXT Expanding Medicaid to previously uninsured adults has been shown to increase detection and reduce the prevalence of depression, but the ways that Medicaid affects mental health care, how effectively it addresses unmet needs, and how those effects differ for those with and without a history of depression remain unclear. METHODS We take advantage of Oregons Medicaid lottery to gauge the causal effects of Medicaid coverage using a randomized-controlled design, drawing on both primary and administrative data sources. FINDINGS Medicaid coverage reduced the prevalence of undiagnosed depression by almost 50% and untreated depression by more than 60%. It increased use of medications frequently prescribed to treat depression and related mental health conditions and reduced the share of respondents reporting unmet mental health care needs by almost 40%. The share of respondents screening positive for depression dropped by 9.2 percentage points overall, and by 13.1 for those with preexisting depression diagnoses, with greatest relief in symptoms seen primarily in feeling down or hopeless, feeling tired, and trouble sleeping-consistent with the increase observed not just in medications targeting depression but also in those targeting sleep. CONCLUSIONS Medicaid coverage had significant effects on the diagnosis, treatment, and outcomes of a population with substantial unmet mental health needs. Coverage increased access to care, reduced the prevalence of untreated and undiagnosed depression, and substantially improved the symptoms of depression. There are likely to be substantial mental health consequences of policy decisions about Medicaid coverage for vulnerable populations.

The Uninsured Do Not Use The Emergency Department More—They Use Other Care Less

There is a popular perception that insurance coverage will reduce overuse of the emergency department (ED). Both opponents and advocates of expanding insurance coverage under the Affordable Care Act (ACA) have made statements to the effect that EDs have been jammed with the uninsured and that paying for the uninsured populations emergency care has burdened the health care system as a result of the expense of that care. It has therefore been surprising to many to encounter evidence that insurance coverage increases ED use instead of decreasing it. Two facts may help explain this unexpected finding. First, there is a common misperception that the uninsured use the ED more than the insured. In fact, insured and uninsured adults use the ED at very similar rates and in very similar circumstances-and the uninsured use the ED substantially less than the Medicaid population. Second, while the uninsured do not use the ED more than the insured, they do use other types of care much less than the insured.