Functional Status Implementation Guide
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Functional Status

Poor quality discharge information is a major barrier to safe and effective transitions. With 45% of Medicare beneficiaries requiring post-acute care (PAC) services after hospitalization, the need for a seamless exchange of health information is great.

In 2014, the Social Security Act was amended to include the Improving Medicare Post-Acute Care Transformation (IMPACT) Act, which required the standardization and interoperability of patient assessment in specific categories for post-acute care (PAC) settings, including long-term care hospitals (LTCHs), home health agencies (HHAs), skilled nursing facilities (SNFs), and inpatient rehabilitation facilities (IRFs). It focuses on standardizing data elements in specified quality measure domains and patient assessment domains for cross setting comparison and clinical information exchange, respectively. The Act requires:

Reporting of standardized patient assessment data through commonly used PAC assessment instruments for LTCHs, SNFs, HHAs, and IRFs Minimum Data Set (MDS)for SNFs Inpatient Rehabilitation Facility – Patient Assessment Information (IRF – PAI) for IRFs LTCH Continuity Assessment Record and Evaluation (CARE) Data Set (LCDS) for LTCHs Outcome and Assessment Information Set (OASIS) for HHAs Implementation of data elements specified in each assessment domain using standardized data elements to be nested within the assessment instruments currently required for submission by LTCH, IRF, SNF, and HHA providers Data to be standardized and interoperable to allow exchange of data between PAC providers, among others, using common standards and definitions to provide access to longitudinal information and facilitate coordinated care.

Expected Users

Interoperability challenges persist in post-acute care; providers are not receiving complete and accurate information in a timely manner, leading to patient harm, adverse outcomes, and additional expense. Failure to exchange accurate, timely data often leads to inefficient workflows, duplicative data entries, and increased risk of patient harm attributable to missing or inaccurate information. Health IT can significantly alleviate this administrative burden by exchanging post-acute care assessments and associated clinical information between care settings to ensure that the receiving care setting has all of the relevant information they need to best treat the incoming patient, improving patient outcomes, reducing provider burden, improving cost efficiencies, and improving workflows. Moreover, it would allow for advanced computability, standardization, usability, and real-time analytics for PAC facilities, enabling broader use by health IT developers, researchers, providers, and payers.

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The PACIO Project is a collaborative effort to advance interoperable health data exchange between post-acute care (PAC) and other providers, patients, and key stakeholders across health care and to promote health data exchange in collaboration with policy makers, standards organizations, and industry through a consensus-based approach.

The primary goal of the PACIO Project is to establish a framework for the development of Fast Healthcare Interoperability Resource (FHIR) technical implementation guides and reference implementations that will facilitate health data exchange through standards-based use case-driven application programming interfaces (APIs).

Content and Organization

The implementation guide is organized into the following sections:

  • Use Case Example Describes an example of its use and provides a high-level overview of expected process flow.
  • Underlying Technologies Describes the different specifications this implementation guide relies on and indicates what developers should read and understand prior to implementing this specification.
  • Profile Highlights and Guidance Provides a closer look at the IG profiles and guidance for constructing profile instances with examples for data exchange.
  • Security and Data Sharing Covers issues concerning security and patient information access and sharing.
  • Artifacts Summary Introduces and provides links to the Capability Statement, IG Resource Profiles, and IG Extension Definitions as well as example profile instances.


This implementation guide relies on the following other specifications:

  • FHIR R4 - The ‘current’ official version of FHIR as of the time this implementation guide was published. See the background page for key pieces of this specification implementers should be familiar with.
  • US Core STU3 - The version of US Core based on FHIR R4.

This implementation guide defines additional constraints and usage expectations above and beyond the information found in these base specifications.