Example Usage Scenarios:

The following are example usage scenarios for this profile:

• Query for OFC percentile observation belonging to a pediatric patient
• Record or update OFC percentile observations belonging to a pediatric patient

Mandatory and Must Support Data Elements

In addition to the Mandatory and Must Support data elements in the IE Core Vital Signs Profile, the following data elements must always be present (Mandatory definition) or must be supported if the data is present in the sending system (Must Support definition). They are presented below in a simple human-readable explanation. Profile specific guidance and examples are provided as well. The Formal Views below provides the formal summary, definitions, and terminology requirements.
Note that the "Differential Table" displays elements unique to this profile and the "Key Elements Table” displays a combined view of elements for this profile and the IE Core Vital Signs Profile.

Each Observation Must Have:

1. a patient
2. a fixed code for head occipital frontal circumference percentile measurement

Each Observation Must Support:

1. a result value

Profile Specific Implementation Guidance:

• • Note that this profile also conforms to the base FHIR Vital Signs Profile.

• The observations MAY have additional codes that translate or map to the Observation code or category codes. For example:
  • providing a local system-specific code
  • providing more specific codes such as 8306-3 - Body height - lying in addition to 8302-2 - Body height. Several additional observation codes are provided in the FHIR core specification vital signs table.

  A code system value SHOULD be supplied for each additional code.

• The observations MAY have component observations. For example, to qualify the vital sign observation, 8310-5 - Body temperature, 8327-9 - Body temperature measurement site (oral, forehead, rectal, etc.) may be used as a component observation. The FHIR core specification vital signs table provides several of these.
• *An Observation without a value, SHALL include a reason why the data is absent unless there are 1) component observations, or 2) reporting panel observations using Observation.hasMember.
  • For further guidance, see the Observation Grouping section in FHIR Specification.
  • Systems that never provide an observation without a value are not required to support Observation.dataAbsentReason.
• *An Observation.component without a value, SHALL include a reason why the data is absent.
  • Systems that never provide a component observation without a component value are not required to support Observation.component.dataAbsentReason.

• Implementers may use this profile as a base for other vital signs in addition to those in this guide.

• Information about the growth chart tables used to determine percentiles SHOULD be supplied in Observation.note.text (for example, 'WHO Males, 0-2 years Chart').
• To represent the raw OFC measurements, use the IE Core Head Circumference Profile.

Quick Start

Below is an overview of the required Server RESTful FHIR interactions for this profile - for example, search and read operations - when supporting the IE Core interactions to access this profile's information (Profile Support + Interaction Support). Note that systems that support only IE Core Profiles (Profile Only Support) are not required to support these interactions. See the IE Core Server CapabilityStatement for a complete list of supported RESTful interactions for this IG.

• See the Scopes Format section for a description of the SMART scopes syntax.
• See the Search Syntax section for a description of the IE Core search syntax.
• See the General Requirements section for additional rules and expectations when a server requires status parameters.
• See the General Guidance section for additional guidance on searching for multiple patients.

IE Core Scopes

Servers providing access to vital signs data SHALL support these IE Core SMART Scopes:

• resource level scopes: <patient|user|system>/Observation.rs

• granular scopes: <patient|user|system>.Observation.rs?category=http://terminology.hl7.org/CodeSystem/observation-category|vital-signs

Mandatory Search Parameters:

The following search parameters and search parameter combinations SHALL be supported:

1. SHALL support searching using the combination of the patient and category search parameters:

   GET [base]/Observation?patient={Type/}[id]&category=http://terminology.hl7.org/CodeSystem/observation-category|vital-signs

   Example:

   1. GET [base]/Observation?patient=1134281&category=http://terminology.hl7.org/CodeSystem/observation-category|vital-signs

   Implementation Notes: Fetches a bundle of all Observation resources for the specified patient and a category code = vital-signs (how to search by reference and how to search by token)

2. SHALL support searching using the combination of the patient and code search parameters:
   • including optional support for OR search on code (e.g.code={system|}[code],{system|}[code],...)

   GET [base]/Observation?patient={Type/}[id]&code={system|}[code]{,{system|}[code],...}

   Example:

   1. GET [base]/Observation?patient=1186747&code=http://loinc.org|29463-7,http://loinc.org|9843-4,http://loinc.org|8289-1

   Implementation Notes: Fetches a bundle of all Observation resources for the specified patient and observation code(s). SHOULD support search by multiple codes. The Observation code parameter searches `Observation.code only. (how to search by reference and how to search by token)

3. SHALL support searching using the combination of the patient and category and date search parameters:
   • including support for these date comparators: gt,lt,ge,le
   • including optional support for AND search on date (e.g.date=[date]&date=[date]]&...)

   GET [base]/Observation?patient={Type/}[id]&category=http://terminology.hl7.org/CodeSystem/observation-category|vital-signs&date={gt|lt|ge|le}[date]{&date={gt|lt|ge|le}[date]&...}

   Example:

   1. GET [base]/Observation?patient=1134281&category=http://terminology.hl7.org/CodeSystem/observation-category|vital-signs&date=ge2020-01-01T00:00:00Z

   Implementation Notes: Fetches a bundle of all Observation resources for the specified patient and date and a category code = vital-signs (how to search by reference and how to search by token and how to search by date)

Optional Search Parameters:

The following search parameter combinations SHOULD be supported:

1. SHOULD support searching using the combination of the patient and category and status search parameters:
   • including support for OR search on status (e.g.status={system|}[code],{system|}[code],...)

   GET [base]/Observation?patient={Type/}[id]&category=http://terminology.hl7.org/CodeSystem/observation-category|vital-signs&status={system|}[code]{,{system|}[code],...}

   Example:

   1. GET [base]/Observation?patient=1134281&category=http://terminology.hl7.org/CodeSystem/observation-category|vital-signs&status=final

   Implementation Notes: Fetches a bundle of all Observation resources for the specified patient and category and status (how to search by reference and how to search by token)

2. SHOULD support searching using the combination of the patient and category and _lastUpdated search parameters:
   • including support for these _lastUpdated comparators: gt,lt,ge,le
   • including optional support for AND search on _lastUpdated (e.g._lastUpdated=[date]&_lastUpdated=[date]]&...)

   GET [base]/Observation?patient={Type/}[id]&category={system|}[code]&_lastUpdated={gt|lt|ge|le}[date]{&_lastUpdated={gt|lt|ge|le}[date]&...}

   Example:

   1. GET [base]/Observation?patient=1134281&category=http://terminology.hl7.org/CodeSystem/observation-category|vital-signs&_lastUpdated=ge2024-01-01T00:00:00Z

   Implementation Notes: Fetches a bundle of all Observation resources for the specified patient and category and _lastUpdated. See the IE Core General Guidance page for Searching Using lastUpdated. (how to search by reference and how to search by token and how to search by date)

3. SHOULD support searching using the combination of the patient and code and date search parameters:
   • including optional support for OR search on code (e.g.code={system|}[code],{system|}[code],...)
   • including support for these date comparators: gt,lt,ge,le
   • including optional support for AND search on date (e.g.date=[date]&date=[date]]&...)

   GET [base]/Observation?patient={Type/}[id]&code={system|}[code]{,{system|}[code],...}&date={gt|lt|ge|le}[date]{&date={gt|lt|ge|le}[date]&...}

   Example:

   1. GET [base]/Observation?patient=1186747&code=http://loinc.org|29463-7,http://loinc.org|9843-4,http://loinc.org|8289-1&date=ge2020-01-01T00:00:00Z

   Implementation Notes: Fetches a bundle of all Observation resources for the specified patient and date and report code(s). SHOULD support search by multiple codes. (how to search by reference and how to search by token and how to search by date)