Question: I-ve been getting Medicaid denials for 2008 diagnosis codes. Wasn't I supposed to start using these codes in October? New York Subscriber Answer: Although 2008 ICD-9 codes officially went into effect on Oct. 1, 2007, some payers are slower to adopt them than others and may require you to continue using 2007 codes until a later date. Coders report that individual Medicaid carriers are requiring them to use 2007 codes as late as April or June of 2008. Other lucky coders say that they-re able to start reporting 2008 codes to Medicaid without denials. What to do: Unless your payer told you otherwise in writing, you should have begun using updated ICD-9 codes Oct. 1. If you receive denials for the updated codes, contact your carrier and verify which code set it requires you to use. If the carrier wants you to report last year's codes, ask for this instruction in writing, including the date that you should begin using the updated codes.