WASHINGTON—New health care reform regulations clarify how health care plans must handle disputed claims, but leave murky a key issue: how a new federal external claims review requirement will work.

The health care reform law mandates that employees in self-funded plans can request a “federal external review” after their request for coverage of a claim or benefit is denied through internal reviews conducted by employers and plan administrators.

“It would be the interjection of a third party into how an employer runs their self-funded plans,” said Andy Anderson, a partner with Morgan, Lewis & Bockius L.L.P. in Chicago.

But the 128 pages of regulations issued last week by the Internal Revenue Service and the Departments of Labor and Health and Human Services provides little detail on how federal external claims review panels will work, experts say.

“It is 4th and long and (regulators) punted on this one,” said Sharon Cohen, an attorney with Towers Watson & Co. in Arlington, Va.

“There will be a lot more detail to be filled in,” Mr. Anderson said.

“We just don't know the details, and here, the detail is everything,” Ms. Cohen added.

Regulators, though, resolved numerous other issues. For example, the regulation updates a 2000 Labor Department rule on the amount of time plan enrollees will have to be notified of coverage decisions involving urgent care.

Under the regulations, enrollees will have to be notified of an urgent care coverage decision within 24 hours of receipt of a claim.

That is a big change from the decade-old Labor Department rule requiring such decisions to be made within 72 hours of receipt of a claim.

The agencies said “electronic communication will enable faster decision-making” compared with a decade ago.

Experts say such a requirement, given the advances in technology, should be able to be met.

“Of all the changes that will have to be made, the easiest case to be made” for faster coverage decisions is for urgent care, said J.D. Piro, an attorney in the Norwalk, Conn., office of Hewitt Associates Inc.

The rules will impose new criteria to avoid conflicts of interest in claims decisions. For example, a health plan could not provide bonuses based on the number of denials made by a claims adjudicator.

In addition, the regulations require that notices of available internal and external claims appeals processes and review be provided in a “culturally and linguistically appropriate manner.”

The requirement to provide notices in a language other than English will be based on the number or percentage of plan enrollees who are literate in a common non-English language. For plans that cover more than 100 participants, the threshold is 10% of plan participants, or 500 participants, whichever is less.

Plans also will have to step up the amount of information provided to enrollees when coverage is denied. For example, sufficient information would have to be provided to enable an enrollee to quickly identify the claim that is involved, including the date of service; the health care provider; the claim amount, if relevant; the diagnosis code and its meaning; as well as the treatment code.

The new requirements generally would kick in Jan. 1, 2011. However, the new rules would not apply to grandfathered plans. For a plan to retain grandfathered status, an employer, among other things, can't ever raise coinsurance requirements or boost premiums paid by enrollees by more than five percentage points.

The claims review and appeal requirements will be another variable for employers to consider when comparing the cost of keeping the grandfathered status of their health care plans or complying with health care reform requirements, Hewitt's Mr. Piro said.

The release of the claims regulations—which comes after rules on coverage for preventive treatment and screenings, grandfathered plans, annual and lifetime dollar limits, and extension of coverage to employees' young adult children—likely will be the last health care reform regulations to be issued for a while, experts say.

“We have had quite a bit in the last few months. But now, there should be a respite,” said Mike Thompson, a principal with PricewaterhouseCoopers L.L.P. in New York.

Many other provisions of the new law kick in much later, reducing the need for quick regulatory guidance.