Health care providers can apply through April 17 to participate in the third ICD-10 testing sample with Medicare Administrative Contractors and the Common Electronic Data Interchange contractor. Application forms are available on the MAC websites, according to CMS. About 850 volunteers representing a cross section of provider, claim and submitter types will be selected to participate in the testing, scheduled for the week of July 20. In addition, testers from the two previous end-to-end testing weeks can participate without reapplying. On Oct. 1, health care providers must begin including ICD-10 diagnosis and procedure codes on Medicare and other health care claims under a final rule issued last July. AHA members can access an updated Executive Action Guide to help with the transition to ICD-10, and visit the CMS website for more information and resources.