Indianapolis ? Findings from a yearlong state insurance investigation of Anthem Inc.’s medical billing are expected to remain confidential until this fall, although the report is largely complete, an Indiana state official said Wednesday.

The state began the review last spring in response to complaints from Indiana doctors who said the nation’s fifth-largest publicly traded health benefits company reimbursed them slowly or inadequately for many claims.

A consultant the Department of Insurance hired to conduct the review submitted 250 pages of confidential findings three months ago, and Indianapolis-based Anthem filed a rebuttal May 8.

But Insurance Commissioner Sally McCarty this month asked consultant Joy Newby & Associates to clarify some sections of its report, turn over more information and make amendments involving disputed facts.

As a result, the findings are not expected to be released until at least September, according to Greg Thomas, the agency’s chief deputy commissioner.

“We sent it back to make a little more user-friendly and clarify some of the points,” Thomas said.

Deborah New, an Anthem spokeswoman, said, “We’ll continue to work closely with the department and cooperate fully.”

Anthem could face fines if investigators conclude it violated fair-practices laws. Under Indiana state law, the company will be required to cover the cost of the review regardless of the outcome.

The investigation in Indiana is in response to complaints by Otolaryngology Associates, an Indianapolis ear, nose and throat practice, and the Indiana Federation of Ambulatory Surgery Centers.

One facet of the investigation is Anthem’s compliance with a 2001 state law requiring insurers to pay provider claims within 30 days for those filed electronically and 45 days for paper claims.

Also at issue are allegations of unpaid or underpaid claims.

The investigation concerns only the 59-year-old Blue Cross and Blue Shield licensee’s operations in its home state of Indiana.

Over the past decade, Anthem has grown to become the Blue Cross licensee in eight other states: Kentucky, Ohio, Connecticut, New Hampshire, Colorado, Nevada, Maine and part of Virginia.

Kansas regulators last year blocked Anthem’s proposal to acquire the Blue Cross plan in that state.

The Kansas Supreme Court has yet to rule on Anthem’s attempt to overturn the decision.

Anthem has enjoyed strong earnings recently because of healthy customer and revenue growth.

In April, Anthem reported a 92 percent increase in first-quarter earnings. The company reported 60 percent growth for all of 2002.