Medicare administrators declined to comment on the doctors' bills or to say whether they were investigating. But experts in laboratory billing said the high frequency of tests was extremely unusual and underscored the need for Medicare to improve oversight of potentially lucrative drug tests to guard against billing for unnecessary procedures.
"Those numbers are ridiculously high," said Dr Stuart Gitlow, acting president of the American Society of Addiction Medicine. "There is no medical indication I can think of that would require such frequency of testing. I can't come up with a scenario at all."
Two of the doctors work together in New London, Connecticut. The third doctor works in Ellington, about 60 miles away. Two of the three, contacted by Reuters, denied any wrongdoing, with one saying he was simply following Medicare's billing rules as he understood them. The third declined to comment.
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Each of the doctors requested only the most expensive and comprehensive drug test, for as much as $94, rather than the simpler $19 one. This was done to improve the accuracy of the results, one said.
'Spigot of money'
Medicare paid medical providers $457 million in 2012 for 16 million tests to detect everything from prescription narcotics to cocaine and heroin, according to the Reuters analysis.
"In some parts of the country every doctor and his cousin is hanging out a shingle to do (addiction) treatment. There's a tailor-made opportunity for ordering a profusion of tests instead of one," said Bill Mahon, former executive director of the National Health Care Anti-Fraud Association.
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"It's like turning on a spigot of money," he said.
Urine and blood tests are potential areas of fraud and abuse because guidelines for drug testing are vague, leaving the frequency of testing to the discretion of the provider. Unlike private insurance companies, which sometimes dispute charges and pay providers only when they have vetted a claim, Medicare almost always pays first and asks questions later.
There is often a legitimate need for such drug tests, to determine whether an addict has relapsed or to ensure that patients prescribed painkillers are taking them rather than selling them.
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In 2011, the average number of older Americans misusing or dependent on prescription pain relievers grew to about 336,000, up from 132,000 a decade earlier, according to the Substance Abuse and Mental Health Services Administration.
Urine drug testing first showed up on the radar screen of Medicare investigators in 2011. Since then the Office of the Inspector General of Health and Human Services, which oversees Medicare, has settled three cases in which it charged providers whose billings for drug tests were deemed excessive.
When Medicare administrators released the payment data for 880,000 health care providers last month, officials said they hoped outside experts would comb through it for possible waste, fraud, and abuse.