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Department of Health and Human Services

Office of Inspector General -- AUDIT

"Review of Claims for Multiple Procedures Performed in the Same Operative Session in Ambulatory Surgical Centers," (A-07-03-02659)

November 21, 2002

Complete Text of Report is available in PDF format (362 KB). Copies can also be obtained by contacting the Office of Public Affairs at 202-619-1343.


The objective of our analysis was to evaluate the effectiveness of carriers’ claims processing systems in identifying payment reductions for multiple Ambulatory Surgical Centers (ASC) procedures for calendar years 1997 through 2001.  Regulations require that when multiple services are provided in the same operative session, the highest paying procedure is reimbursable at the full payment rate while the other procedures are reimbursable at one-half the normal payment rate.  Our analysis showed that Nationwide Mutual Insurance Company’s (previous contractor) systems failed to identify such instances, which resulted in provider overpayments for calendar years 1997 through 2001of $150,751.  Included in the identified overpayments is approximately $31,211 in beneficiary overpayments for coinsurance.  Most of the overpayments occurred because the carrier’s processing system did not identify multiple procedures performed during the same session when submitted on separate claims.  Palmetto GBA is assuming the task of collecting overpayments because it has the current contract for this Part B Medicare claims processing area.