A number of CMS Limited Data Set (LDS) files are released first as a Proposed Rule file and then as a Final Rule file. They include:
- MedPAR - Hospital (National),
- MedPAR - Long-Term Care Hospital,
- Hospital Outpatient Prospective Payment System (OPPS),
- Hospital Outpatient Prospective Payment System (OPPS) – Partial Hospitalization Program,
- End Stage Renal Disease Prospective Payment System (ESRD PPS), and
- Ambulatory Surgical Center (ASC) Payment System.
The release of these files coincides with the publication of Proposed and Final Rules published in the Federal Register. The Proposed Rule files are available so analysis can be done and comments can be made about proposed changes to the payment system.
Both the Proposed Rule and Final Rule versions of the files contain the same data elements and reflect the same dates of service. However, the final rule includes an additional 3 months of claim run off. In general, there will be roughly 2-3% more claims appearing in the Final Rule than in the Proposed Rule.
Information about the latest years available of the files can be found in the CMS LDS Worksheet found on the Limited Data Set (LDS) Files webpage.