About 10 percent of claims filed under ICD-10 have been denied since the coding vocabulary became the norm on October 1, the Centers for Medicare and Medicaid Services said on Thursday, though only a small number of those denials were due to coding errors.
Of 4.6 million total claims submitted per day, 2 percent were rejected due to incomplete or invalid information, CMS said.
CMS released the metrics on claims submitted from October 1 through October 27.
Invalid ICD-10 codes were the basis for rejecting .09 percent of claims, and .17 percent of total claims submitted based on end-to-end testing.
Total claims rejected due to invalid ICD-9 codes represented .11 percent of submissions and .17 percent of total claims submitted based on end-to-end testing.
Total claims denied were 10.1 percent of total claims processed, CMS said.
Before the change, CMS had said it would not reject claims as long as they were coded using the correct ICD-10 family. Healthcare providers welcomed that since the 70,000 codes included ICD-10 mean they have to be more specific than ever with their coding.
CMS expects to release more information on the ICD-10 transition in November.
Since the transition, claims are processing normally. Medicare claims take several days to be processed and, by law, Medicare must wait two weeks before issuing a payment. Medicaid claims can take up to 30 days to be submitted and processed.