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This page will provide explanations of, and links to, the regulations which support the policy and technical information contained in the OASIS web site.

The two regulations relating to the collection and reporting of OASIS data were published in the Federal Register on Monday, January 25, 1999.  The OASIS collection regulation (HCFA-3007-F) begins on page 3764 of the January 25, 1999  Federal Regulation publication.  The OASIS reporting regulation (HCFA-3006-IFC) begins on page 3748 of the same publication.

In a Federal Register notice published June 18, 1999, CMS announced the effective date for the mandatory use, collection, encoding, and transmission of OASIS data for all Medicare/Medicaid patients receiving skilled services.  Mandatory collection and transmission of OASIS data was delayed in order to ensure the proper balance between preserving individual privacy and fulfilling the statutory requirement to improve quality and pay providers fairly.  Following a comprehensive review of these issues, CMS is taking extra precautions beyond its already stringent privacy protections to guard privacy while maintaining the legitimate focus of OASIS.  In addition, a companion notice concerning the OASIS System of Records (SOR) was published.  The SOR includes the Patient Privacy Notices, which are also listed for you separately below.  A modified SOR was published December 27, 2001 to allow a new routine use authorizing disclosure to national accrediting organizations that have been approved by CMS for deeming authority for Medicare requirements for home health services.  

Since the Medicare Prescription Drug Improvement and Modernization Act of 2003 (MMA) was signed, we have published several Survey and Certification memoranda to clarify various aspects of Section 704 which temporarily suspends the requirement that Medicare-approved HHAs collect OASIS data on non-Medicare/non-Medicaid patients.  For your convenience, these changes are included in the Patient Classification Table in the download below.  For patients receiving personal care only services, regardless of payor source, we are delaying the requirements regarding OASIS until further notice.  The study mandated by Section 704 of the MMA is now complete and available in the downloads section below.

See the downloads below for the Federal Register notices mentioned above related to the use of OASIS and the SOR notices.

Final OASIS Reporting Regulation published 12/23/2005

CMS has published the final reporting regulation for OASIS reporting in the 12/23/2005 Federal Register.  The regulation goes into effect 6/21/2006.  The regulation:  Medicare and Medicaid Programs:  Reporting Outcome and Assessment Information Set Data as Part of the Conditions of Participation for Home Health Agencies, makes the following changes:

  • Revision of the standard in 42 CFR 484.20(a).  The regulation allows 30 days from the date of the assessment (M0090) is completed for the agency to encode and submit OASIS data.
  • Removes the requirement in 42 CFR 484.20(c)(1) to “lock” data within 7 days of assessment.
  • Redesignates the requirement in 42 CFR 484.20(c)(2) as 484.20(c)(1).  This requirement provides that OASIS data must be transmitted in a format that meets the data format standard specified in 42 CFR 484.20(d).
  • Redesignates the data submission requirements at 484.20(c)(3) as 484.20(c)(2) and removes reference to reporting requirements for existing agencies in 1999.
  • Redesignates the requirement at 42 CFR 484.20(c)(4) as 484.20(c)(3).  This requirement provides that HHAs must transmit data using electronic communications software that provides a direct telephone connection from the HHA to the State Agency or CMS OASIS contractor.
  • Addition of a new paragraph 484.20(c)(4) to include the CMS-assigned branch identification number as applicable.

See Download Below for the Regulation:  Medicare and Medicaid Programs:  Reporting Outcome and Assessment Information Set Data as Part of the Conditions of Participation for Home Health Agencies