Researchers working with the outpatient claims data are often interested in calculating the amount paid by Medicare for a particular claim. The total Medicare payment typically can be determined either by using the “Claim Payment Amount” (PMT_AMT) or by summing the “Revenue Center Payment Amount” (REVPMT) for each revenue center. However, researchers have found discrepancies in the amounts when comparing these two approaches.
When differences are observed between these two values, it is likely due to how the claim was processed and the payment system under which the claim was paid. Most outpatient services are paid under the Outpatient Prospective Payment System (Outpatient PPS or OPPS). However, certain types of bills and Healthcare Common Procure Coding System (HCPCS) codes may not be priced using the OPPS. Claims paid under OPPS are processed through an application called the Outpatient PPS Pricer. The Pricer generates values in the claims files, including revenue center payments. Claims that are not paid under OPPS may not be run through the Outpatient PPS Pricer. Therefore, these claims may not include data in some values, including revenue center payments. Below is a note contained in the data dictionary for the revenue center payment variable that explains when a claim will not be processed through the Outpatient PPS Pricer.
This field is populated for those claims that are required to process through Outpatient PPS Pricer. The type of bills (TOB) required to process through are: 12X, 13X, 14X (except Maryland providers, Indian Health Providers, hospitals located in American Samoa, Guam and Saipan and Critical Access Hospitals (CAH)); 76X; 75X and 34X if certain HCPCS are on the bill; and any outpatient type of bill with a condition code '07' and certain HCPCS. These claim types could have lines that are not required to price under OPPS rules so those lines would not have data in this field.
If revenue center level payment values are necessary for a study question, researchers may consider excluding all claims that were not paid under OPPS. Fortunately, the claim level payment value should appear for all claims including those not paid under OPPS. In situations where the above explanation does not explain a discrepancy, ResDAC considers the 'Claim Payment Amount' to be the more reliable field. While the discrepancy in payment amounts between the claim and revenue center levels does occasionally occur, it is not common.