What may seem obvious — the notion of medical necessity — isn't soeasy to distill into policy rules. (Photo: Getty)

Progressive Democrats have rallied around “Medicarefor All,” a single-payer health plan popularized bySen. Bernie Sanders (I-Vt.). Now, some ofWashington's official bean counters are trying to add a newframework around what it might look like. The picture they offerhighlights just how complicated that shift might be.

Areport released Wednesday by the nonpartisan CongressionalBudget Office outlined a veritable laundry list of options andtechnicalities lawmakers would need to consider if they are seriousabout such a proposal.

“The conversation about single-payer is getting more in theweeds, more detailed, which is a good thing because it's such acomplicated issue,” said Jodi Liu, an associate policy researcherat the Rand Corp. who studies single-payer proposals.

Related: CBO: Medicare for All a 'majorundertaking'

The takeaway: There's a lot left to be answered about theconcepts of Medicare for All specifically and the more broadcategory of single-payer before policymakers and voters can comeclose to understanding what it would mean in practice. The term“single-payer” generally refers to a system in which health care ispaid for by a single public authority.

“Even single-payer systems around the globe vary from each otherin many, many ways,” said John McDonough, a Harvard health policyprofessor who helped draft the Affordable Care Act. “There's justso many aspects of it that differ from a Canada to a Sweden to aTaiwan — and those are all intensely consequential.”

The report comes as this once-lefty pipe dream becomesofficially mainstream.

Medicare for All has been name-checked by Democrats running for president. On Tuesday,Democrats and Republicans alike put the proposal under themicroscope at a House Rules Committee hearing. And that won't be the last timethat happens. House Ways and Means Committee Chairman Richard Neal(D-Mass.) said he, too, intends to hold a hearing on the issue thissession. Meanwhile, Sanders' latest Medicare for All bill,reintroduced in the Senate in April, and a similar House bill, have 14 and 108 co-sponsors,respectively.

Let's break down the most crucial issues raised by the CBOreport — what single-payer might cover, why “what it would cost”isn't easy to determine and what it could mean for how Americansget their health care.

Medicare for All backers say the program wouldcover all medically necessary services. But what does that trulymean?

What may seem obvious — the notion of medical necessity — isn'tso easy to distill into policy rules. And different single-payersystems around the world handle the benefits question differently,the CBO noted.

For instance, Canada doesn't cover prescription drugs, but theUnited Kingdom and Sweden do. Of those three, only Sweden fullycovers long-term support services, according to the report.

There are two questions at the heart of it, said RobertBerenson, a health policy analyst at the Urban Institute, aleft-leaning think tank.

What benefits would be covered? Would it include dental care orprescription drugs or vision, as Sanders' bill would? And, how doesone determine the discrete services included within those benefitscategories?

Single-payer architects could look at existing standards, suchas the so-called essential health benefits that govern Obamacarehealth plans, to determine what's covered. They could be moregenerous by including long-term care, which isn't currently coveredby Medicare or most private insurance plans.

Even the two “Medicare for All” bills in Congress have slightlydifferent takes. Though both provide for long-term support andservices, they diverge on how to pay for it. Sanders' bill covers only at-home long-term care and keepsMedicaid intact for services provided in institutions. The House bill by Rep. Pramila Jayapal (D-Wash.) covers both.

And there are questions about new medical treatments, and how todetermine whether they provide added value. The CBO reportsuggested some kind of “cost-effectiveness criterion” coulddetermine what the government is willing to cover. In practice,though, that standard could be difficult to develop and fall victimto political lobbying or trigger contentious debate.

Separately from the CBO report, McDonough noted, controversialmedical services could bring up different kinds of politicalbaggage — whether this plan would cover abortion, for instance,likely would change the single-payer debate.

Next: Single-payer health care would probably requirenew taxes. Just what level of taxes, though, and whom they'd hithardest remain open questions.

Notably, the single-payer report avoids a question that criticsfrequently surface: How much would this cost? How would you pay forit?

That's because there's no uniform cost estimate for single-payerand no easy formula to apply.

For one thing, the price tag depends on what services arecovered — something like long-term care would make the idea muchmore expensive.

There's also the question of cost sharing. In some single-payersystems, people must pay a copay, meet a deductible or pay apremium as part of the health plan. That would alleviate some needfor new taxes.

“I don't think you can put numbers on it until someone defines abenefit package and defines cost sharing,” Berenson said.

The current Medicare for All bills eschew cost sharing.Other health reform proposals would keep premiums intact to helpfoot some of the bill.

The CBO report suggests that new taxes would likely play a rolein financing a new single-payer plan. But what kind of taxes — apayroll tax, an income tax or a sales tax, for instance — has notyet been stipulated. And each would have differentconsequences.

The single-payer approach could bring down healthexpenses, or at least increase value. But how effectively it woulddo so — and its larger economic impact — would depend on otherdesign choices.

Single-payer backers dismiss the “pay-for” questions because,the reasoning goes, this approach would save lots of money in otherways, ultimately making it a good deal.

Yet again, though, the CBO said, whether that actually happensdepends on the system's design.

By eliminating most private insurers, a single-payer systemwould likely slash hospitals' administrative overhead. Thegovernment could then pay a rate that better reflects reducedhospital costs, according to the CBO report.

But, ultimately, the single-payer bottom line depends on whatthe system pays hospitals, doctors and drug companies for differentservices and products. That answer also would inform other economicassessments — ascertaining, for instance, how single-payer affectsa small town where the hospital is the main employer.

Even without clear answers, outlining those questions moves theball, Liu said.

“This area is moving really fast,” she said. “To me, it seemslike this is the beginning of a longer conversation.”

Kaiser Health News isa nonprofit news service covering health issues. It is aneditorially independent program of the Kaiser Family Foundation,which is not affiliated with Kaiser Permanente.

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