Steps aimed at cutting Medicare fraud and payment errors in half over the next four years were announced by U.S. health officials on Monday.

The Medicare program, which assists the disabled and elderly, said it is collecting more information from the health insurers that process claims under the program from hospitals, doctors and other health care providers.

Mark McClellan, head of the agency that oversees the program, said the additional information will allow officials to make sure patient claims are submitted and paid properly.

“The majority of providers are honest and want to make sure they file their claims correctly so they can be paid timely, and we’re taking new steps to work with our contractors to make sure that happens,” McClellan said.

Using the new data analysis, Medicare officials reviewed 120,000 claims and projected $19.9 billion was spent on improper payments in 2004, leading to an overall error rate of 9.3 percent. Officials said they aim to use the new system to reduce that rate by more than half by 2008.

Most problems were due to insufficient paperwork filed with a claim or a lack of response to the agency’s request to see medical records. Unnecessary services and errors in codes used for a claim were also a problem, officials said.

The Centers for Medicare and Medicaid Services has been struggling with fraud for years. Scammers abuse the program most often by either charging Medicare for services they never provide or billing for unnecessary treatments and supplies, according to the Government Accountability Office (GAO).

In 1990, the GAO, which conducts investigations for Congress, said Medicare was at “high risk” for abuse, citing the program’s large size, complexity, and weak management. Medicare processes more than 1 billion claims each year, according to the agency.

Since then Medicare officials have aimed to implement GAO’s recommendations. In 2000, the GAO said such efforts were “promising” but that a better system to measure errors is needed. Two years later, it said Medicare had made “good progress” but needs to do more.

As part of Monday’s announcement, McClellan said health insurers will be held more accountable as the agency reviews larger, more detailed claims data that were not available before 2003.

“We’ve got a much better ability to take specific action with specific contractors to reduce the errors,” he said.

Insurers that contract with Medicare to process claims include Cigna Corp., WellPoint Inc. and privately held Blue Cross Blue Shield, among others.