Hospitals may submit multiple claims for some hospitalizations. This article provides guidance for counting distinct inpatient hospitalizations and for sequencing claims for each distinct hospitalization found in the inpatient Research Identifiable File (RIF) and Limited Data Set (LDS) files. This guidance is not applicable to the MedPAR because each record in that file is already a distinct hospitalization.
Inpatient LDS KnowledgeBase Articles
Researchers working with the Research Identifiable (RIF) versions of the MedPAR or Inpatient and Skilled Nursing Facility (SNF) claims may find records that do not appear to correspond to the year of the file. These instances can usually be explained by how stays or claims are included in the files during file creation.
Most charges for observation stays that result in an inpatient admission within 3 days of the observation period will be found in the Inpatient file. Two exceptions are described in the CMS Medicare Claims Processing Manual, section 40.3.B.
Beginning in 2008, some hospital provider numbers appearing in the claims contain a “V” in the fifth position of the six-digit Medicare Provider Number. Usually, the fifth position is a number, not a character. These hospital provider numbers appear in the MedPAR, Inpatient and Outpatient files for both RIF and LDS versions. ResDAC recommends that researchers remove these claims.
Researchers who are interested in studying inpatient utilization (e.g. hospital stays) have two options: the Inpatient claims file or the Medicare Provider Analysis and Review (MedPAR) file. It is important to note that the differences between the two files will vary depending on whether a researcher is interested in the Research Identifiable File (RIF) or Limited Data Set (LDS) versions of the two files.
Please note that the information below applies to the claim-level files, but not to the stay-level file (the LDS MedPAR).