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A landmark study published Thursday showed that when Oregon expanded Medicaid, those who gained coverage used the emergency room more than the uninsured.

Officials out in Oregon don't dispute the results -- but they do argue that the study doesn't offer a great picture of what's happening out there right now. The Science study looks at a 2008 expansion. A lot has changed in the past five years. In fact, over the past two years, Oregon has actually seen a decline in Medicaid emergency department visits this past year -- and attributes that to big changes the state has made to how it delivers care to Medicaid patients.

"That study was looking at the old system and the old way of doing things," says Sean Kolmer, deputy chief of policy and programs for the Oregon Health Authority, which runs the state Medicaid program. "It reflects what we knew would happen. But that's the old world."

Oregon is now testing a new world of Medicaid, one in which they set a stringent cap on expenditures for each enrollee -- and try to hit it by providing more cost-effective health care. That's made emergency-room visits one key metric that the state is trying to drive down, especially in situations where the patient could be seen in a less expensive, primary-care setting.

I went out to Oregon just about a year ago, when the state had divided its Medicaid program up into 15 regions, each of which was given a lump-sum amount to pay for their enrollees' health care. These regions, known as "coordinated care organizations," are then left to figure out a plan for how to keep to that spending target. The targets are phased in, becoming increasingly difficult to meet over the next few years.

A year later, Oregon is starting to analyze progress. One way that Oregon's CCOs have hit their targets is by reducing the exact same type of medical care that's at the heart of the Science study: primary care delivered in an emergency-department setting. In year one, the CCOs saw a 9 percent reduction in emergency-department visits among Oregon's Medicaid population. You can see the reduction in this chart, which looks at the number of emergency-department visits per 1,000 member months.

Emergency-department spending decreased by 18 percent in Oregon's Medicaid program, when the 2013 study period was compared to a 2011 benchmark. And, says Kolmer, state health officials' data show that much of the reduction has come from moving primary care outside the emergency department.

"Most of the things that are being cut are management of chronic conditions," he says. "It's things like congestive heart failure and COPD. You shouldn't see, for example, a kid with asthma going to the ED. That's completely preventable."

One way that Oregon's CCOs are cutting down on emergency-department use is by stationing community health workers in the hospitals themselves, to divert less urgent patients to less costly settings. I asked Kolmer whether these workers faced challenges, whether patients were at all resistant to being told to get their care elsewhere.

"Absolutely. We're talking about changing behavior at every level," he responded. "It's behavior change for the provider, being allowed to do different things. And it's behavior change for the patient. Everyone has got to start changing. Members have to engage and be accountable for their own care." 

Oregon's Medicaid program is now beginning to absorb 130,000 new patients who have come in through the new health-care law's Medicaid expansion. And Kolmer is confident that as these previously uninsured people gain access, they won't look like the patients in the last expansion. He hopes they'll act more like current enrollees and continue to drive down emergency-department trips.

"Coverage is essential, definitely," he says. "You have got to get people into the system. But we think without the CCOs, we wouldn't be able to do it in a way that was sustainable. Now we've got that chance." 

KLIFF NOTES: Top health policy reads from around the Web.

Adding a baby to your Obamacare plan is really difficult. "There's another quirk in the Obama administration's new health insurance system: It lacks a way for consumers to quickly and easily update their coverage for the birth of a baby and other common life changes. With regular private insurance, parents just notify the health plan. Insurers will still cover new babies, the administration says, but parents will also have to contact the government at some point later on. Right now the HealthCare.gov website can't handle such updates." Ricardo Alonso-Zaldivar in the Associated Press.

DOJ rejects nuns' petition against contraceptives mandate. "The Obama administration on Friday offered a vigorous defense of the Affordable Care Act's 'birth control mandate,' disputing as unfounded the religious challenge that led a Supreme Court justice to partially block the provision from taking effect this week.  In court papers filed ahead of a 10 a.m. deadline, the Justice Department contends that the regulations in question contain language allowing certain non-profit groups to easily opt out of paying for contraception as part of employee health insurance plans." Ben Goad in the Hill. 

Here's why the emergency room has a certain allure. "First, low-income individuals are likely to attach a high 'time cost' to primary care visits. Relative to their middle- and high-income counterparts, these patients face greater barriers when it comes to taking time off of work for a scheduled appointment, arranging transportation, child care, and the like. The hospital might offer easier access than outpatient clinics, and, in the emergency department, it’s less likely that they’ll be asked to return for follow-up visits." Adrianna McIntyre in the Incidental Economist