The American Medical Association and 99 other state medical, medical specialty and professional associations are asking CMS acting Administrator Andrew Slavitt to have the agency improve transition plans for the Oct. 1 conversion to ICD-10 diagnostic and procedural codes.“By itself, the implementation of ICD-10 is a massive undertaking,” the AMA and fellow signatories said in a seven-page letter Wednesday. “The undersigned organizations remain gravely concerned that many aspects of this undertaking have not been fully assessed and that contingency plans may be inadequate if serious disruptions occur on or after Oct. 1.”

As evidence of the need for plans, the AMA-led group pointed to last month’s release of mixed results from a first round of so-called end-to-end testing of the Medicare claims flow.

The testing, conducted between Jan. 26 and Feb. 3, “demonstrated that CMS systems are ready to accept ICD-10 claims,” the CMS said in a statement announcing the results.

Fewer than 10 claims out of nearly 15,000 submitted by 661 providers, suppliers and clearinghouses were rejected due to CMS system errors. Overall, including errors by submitters, the testing produced an 81% acceptance rate, the CMS reported. So 19% of claims voluntarily submitted by the provider and claims processors—more than 2,700—bounced, almost all due to mistakes made by claims submitters.

The AMA pointed out in the letter the normal acceptance rates for Medicare claims runs between 95% and 98%.

“Given that Medicare processes 4.4 million claims per day, even a small change in this acceptance rate will have an enormous impact on the system and payment to physicians,” the letter said. It asked for more details about the errors and what steps need to be taken to correct them.

It also warned that the first-round testers were volunteers and so possibly those who are “most confident of their preparation” and thus will not be representative of post-Oct. 1 submitters industry wide.

“The likelihood that Medicare will reject nearly 1 in 5 of the millions of claims that go through our complex healthcare system each day represents an intolerable and unnecessary disruption to physician practices,” AMA President Dr. Robert Wah said in a release accompanying the letter. “Robust contingency plans must be ready on day one of the ICD-10 switchover to save precious healthcare dollars and reduce unnecessary administrative tasks that take valuable time and resources away from patient care,” Wah said.

The group also urged the CMS and the Office of the National Coordinator for Health Information Technology at HHS to look into whether electronic health-record system developers, who have been delayed in upgrading their systems to the more stringent 2014 Edition requirements for the EHR incentive payment program, will be experiencing similar delays with converting their systems to ICD-10.

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