October 6, 2003

Medicare: Discrepancy in Hospital Outpatient Prospective Payment System Methodology Leads to Inaccurate Beneficiary Copayments and Medicare Payments

When CMS published the final rule updating the OPPS payment rates for 2003, the agency stated that it used the methodology implemented in 2002 for determining 2003 copayments. However, in the course of other ongoing work, we found several APCs for which copayment amounts increased from 2002 to 2003, contrary to the methodology implemented in 2002. For a federal agency to adopt a new position or payment methodology that is inconsistent with existing rules and regulations, it must follow Administrative Procedure Act rulemaking requirements, which generally include publishing its intentions and allowing for public comment. Because of our concerns about this methodological discrepancy, we discussed the issue with CMS staff in May 2003. Thereafter, in its August 2003 proposed rule setting forth the 2004 OPPS payment rates, CMS stated that it would revise and clarify the copayment methodology implemented in 2002, and that this revised methodology would be used to calculate copayment amounts beginning in 2004.