This page is part of the Situational Awareness for Novel Epidemic Response (v1.0.0: STU 1) based on FHIR R4. This is the current published version. For a full list of available versions, see the Directory of published versions

Sample Measure Library

The Public Health Measure Library profile provides access to the resources needed to execute a defined Public Health Measure. Each conforming measure must reference at least one, and may reference multiple conforming Library resources. These libraries provide access to the Terminology, resources essential for computing the measure.

Software Component Name

Computer friendly names enable developers to create software tools that facilitate measure implementation and automation. This profile recommends transforming the title into a name by removing spaces and special characters (any character other than A-Z, a-z and 0-9), using PascalCase to separate boundaries between words. This allows the name to be used in most computing languages and as the id for the resource in systems where user defined identifiers are supported for id values.

1. Library.name shall be present.
2. Library.name should match the pattern [A-Z][A-Za-z0-9]+.
3. Library.id should be equal to Library.name.

Canonical URL

The canonical URL is a unique identifier which represents the Library within Measure resources. Tooling for FHIR (e.g., the FHIR IG Publisher, SUSHI, Simplifier) follows a protocol for automatically constructing these URLs. This guide makes several recommendations for URLs used by a publisher. The example below is used to illustrate the recommendations

 https:\//example.com/saner/covid19ValueSets/Library/MyLibraryName

1. All Library URLs for libraries published by the same organization should have the same base URL. The Base URL part should be memorable. In the example above, https:\//example.com/saner is the base URL.
2. The base URL should be less than 40 characters in length.
3. The penultimate path part of the URL may be used to categorize libraries in some way, e.g., by topic (e.g., ValueSets, functions). In the example above, covid19ValueSets is the category.
4. The last path part in the URL should be Library. Following this recommendation simplifies the use of FHIR IG Development tools to generate Measure resources. In the example above, the last path part is Library.
5. The computable name given in the Library should be the last part of the URL. Again, this simplifies measure development using existing FHIR IG Development tools. In the example above, MyLibraryName is the name of the library.
6. The URL should resolve to an HTML page that describes the measure, or provides access to it as a FHIR Resource and ideally, would return HTML, XML or JSON representations based on the requested mime type.

Versioning

Library resources can change over time. This guide requires that the Library version information recorded be performed as follows:

1. A library shall do one of the following:
   • be recorded in the form defined by Semantic Versioning, e.g.: version 1.2.3 is the third patch to the second minor update of the first major release, or
   • be recorded by date using ISO 8601 format with hyphens and no time component, e.g.: 2020-07-25 for the measure released on July 25, 2020.
2. If versions can be updated more frequently than by day, a publisher shall use semantic versioning.

The use of semantic versioning is preferred because this is the form required in FHIR implementation guides, and it enables support for versioning of libraries using FHIR Implementation Guide tools. This is also the format for versioning that has been the most widely adopted by the IT industry.

Status of a Library

This profile requires that the publication status of a library be reported (this is a general requirement of all Library resources), and furthermore, that it’s experimental status shall also be reported.

The usage of status values is described below:

draft

The library is presently under development. Libraries presently under development shall also be recorded as being experimental.

active

The library is ready for, or being used, either in pilots or production. The experimental status for the measure shall be used to distinguish between libraries that are being piloted (experimental=true) or in production (experimental=false).

retired

The library should no longer be used in production. Libraries which are retired before ever becoming active in production shall have experimental=true, while those which have been available for production use shall have experimental=false.

Libraries which have been used in the past should remain available for access for use when data has been used in production to enable systems to interpret historical data recorded using the measure.

Library Publication

A library is published by some appropriate authority, for example a governmental agency focused on public health or emergency response, or an organization working with such a governmental agency. Libraries for situational awareness are not expected to endure a ballot process, but will instead be created by authorities using a well established governance process. The reason for this is that as the emergent situation progresses, new libraries will be needed as the situation changes, or existing libraries may need to be updated to address issues found during use.

Libraries are published by organizations rather than individuals. This profile requires that the organization be identified in Library.publisher, and furthermore, that there is at least one organizational e-mail address which can be used to contact that publisher about the Library in Library.contact