Experts say that only a very small number of health care providers file fraudulent claims against the Medicare system. But increasing attention to the issue, as well as increased prosecutions by U.S. attorneys in each state, is sending a message to those who might otherwise consider fraudulent billings.

Prosecutors are achieving impressive conviction rates.

• Prosecutors in 13 states won every case they brought before the courts.

• But some states, such as South Dakota, Vermont and Alaska have filed few, if any, cases -- with none ending in convictions.

• Otherwise, prosecutors were least successful in New Hampshire, with 25 percent of cases ending in convictions; Wisconsin, 40 percent; Georgia, 47 percent; Montana and Utah, 50 percent each; New York, 57 percent and Minnesota, 58 percent.

• Most other states had conviction rates generally ranging from 80 percent to 99 percent.

On average, prosecutions resulting in convictions have increased from 73 percent in 1993 to 87 percent in 1997.

Source: Peter Eisler, "Feds' War Against Health Care Fraud Escalates," USA Today, February 23, 1999.