According to the Centers for Medicare and Medicaid Services (CMS), it was able to accept nearly all of the more than 127,000 ICD-10 test claims submitted by approximately 2,600 providers, suppliers, billing companies and claims clearinghouses who participated in its test in early March.

Nationally, CMS said it accepted 89 percent of the test claims, with some regions reporting acceptance rates as high as 99 percent. The normal Medicare Fee-for-service (FFS) claims systems acceptance rates are 95 to 98 percent.

In addition, CMS reported that testing did not identify any issues with the Medicare FFS claims systems, and those who sent in accepted claims got the system generated acknowledgements just as intended. It also noted that the actual success rate might have been even higher if not for the fact that many testers also submitted intentionally faulty claims to check if these would be rejected by the system as expected.

However, this testing is not the end-to-end testing many providers had asked for. It only tested if CMS’s system could accept ICD-10 coded claims without an issue. It did not test if it could then take each claim all the way through to theoretical payment without problems.

In addition, clearinghouses, which have a strong business need to prove themselves as better able than individual providers to submit successful claims, were the largest group of testers. Together, these expert claims submitters sent in approximately half of all the tested claims, and CMS did not release whether successful claims submissions varied by the type of group submitting the claims.

For small margin providers with complex cases, such as pediatricians, the success rate for submitting claims that would be accepted and then processed without problems all the way through payment might be lower. Indeed, a study published in Pediatrics the day after CMS released its successful test results did find that about 8 percent of the types of codes pediatricians would bill might prove problematic and this could result in significant financial disruption and administrative headaches for practices.