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OASIS Data Sets


March 05, 2019

CMS is updating the Quality Improvement and Evaluation System

Starting in March, the Quality Improvement and Evaluation System (QIES), Certification and Survey Provider Enhanced Reports (CASPER) and Automated Survey Processing Environment (ASPEN) will undergo a series of modernizing enhancements. Once updated, the system will be called the Internet Quality Improvement and Evaluation System (iQIES). The iQIES system will not change how providers currently submit data to CMS.

The new enhancements in iQIES are based on user research and testing and feature a human-centered design and agile development practices. CMS is phasing in the iQIES system beginning with Long Term Care Hospitals (LTCH). Several updates to the QIES- Assessment Submission and Processing (ASAP) system are also planned. The Cloud-based solutions will also make it easier for users to receive support and use the system.

iQIES Details:

  • Users will no longer need a virtual private network (VPN) or CMSNet to access the system. iQIES is Internet-facing and maintains the latest system architecture and security standards.
  • System enhancements support flexible and user-friendly data reports for providers, allowing them to use real-time data for care planning as well as quality monitoring and improvement.
  • Users can access important information for work anywhere, at any time, on mobile devices, laptops, and tablets.

CMS will be sharing more information about iQIES such as onboarding, stakeholder engagement opportunities, training, and general updates soon!

If you have questions, please contact our service desk at: or by phone: 800-339-9313.

December 20, 2018

Effective January 1, 2019, OASIS-D is the current version of the OASIS data set. The OASIS-D instrument was approved by the Office of Management and Budget (OMB) on December 6, 2018. The final OASIS-D instrument is available in the Downloads section, below. The final OASIS-D Guidance Manual is available on the OASIS User Manuals webpage.

August 4, 2017

OASIS-C2 2018 Guidance Manual Available

The 2018 guidance manual for the OASIS-C2 version of the OASIS data set is available in the Downloads section below and on the OASIS User Manuals webpage. This version corrects errata from the previous version and contains clarifications about the One Clinician Rule. The effective date is January 1, 2018.


  • The OASIS-D is effective January 1, 2019.
  • This version includes multiple new standardized items (GG0130, GG0170a-b, d-s, J1800, J1900) to support measurement domains mandated by the Improving Medicare Post-Acute Care Transformation (IMPACT) Act. New items were also added for standardization to align with the Inpatient Rehabilitation Facility-Patient Assessment Instrument (IRF-PAI), the Long-term Care Hospital assessment set, and the Minimum Data Set( MDS): GG0100 Prior Function and G0110 Prior Device Use
  • OASIS item M1311 was modified to support a new standardized pressure ulcer measure to replace the current standardized pressure ulcer measure.
  • Several items were removed, including select data elements at different time points, to reduce provider and patient burden.
  • The complete set of OASIS-D data items can be found in the Downloads section below.

OASIS and Medicare Home Health PPS

The most current information about Home Health PPS and use of OASIS can be found on the Home Health PPS web page via the link in the “Related Links” section below.