Despite a spike in rejected Medicare claims, theimplementation of the National Provider Identifier number requirement has metwith no huge problems so far, according to the Centers for Medicare &Medicaid Services.

About a quarter (24%) of Medicare claims and Medicaidclaims (26%) were rejected on May 23, the first day the regulation took effect,according to an analysis by Emdeon Business Services. This compares to usualrates of 6% and 4%, respectively.

Most of the rejections stemmed from the use of oldnumbers being used to identify secondary providers. CMS has introduced atemporary measure to allow these claims if providers have extreme difficultyobtaining the NPI numbers for secondary providers.

While there do not appear to be any majorissues with the new system, a CMS spokesman said the program is still too newto draw any conclusions. The extent of any problems should become clearer inthe next few weeks, he said. The new rule governs Medicare and Medicaid claimsmade under the Health Insurance Portability and Accountability Act of 1996(HIPAA).