Release 4 Value Set

FHIR Infrastructure Work Group Maturity Level: NNormative (from v4.0.0) Use Context: Any
This page has been approved as part of an ANSI standard. See the Observation Package for further details.

This is a value set defined by the FHIR project.


Defining URL:

Used to specify why the normally expected content of the data element is missing.

Committee:FHIR Infrastructure Work Group
OID:2.16.840.1.113883.4.642.3.5 (for OID based terminology systems)
Source ResourceXML / JSON

This value set is used in the following places:

This value set includes codes from the following code systems:


This expansion generated 21 Jan 2021

This value set contains 15 concepts

Expansion based on version 4.0.1

All codes from system

0unknownUnknownThe value is expected to exist but is not known.
1  asked-unknownAsked But UnknownThe source was asked but does not know the value.
1  temp-unknownTemporarily UnknownThere is reason to expect (from the workflow) that the value may become known.
1  not-askedNot AskedThe workflow didn't lead to this value being known.
1  asked-declinedAsked But DeclinedThe source was asked but declined to answer.
0maskedMaskedThe information is not available due to security, privacy or related reasons.
0not-applicableNot ApplicableThere is no proper value for this element (e.g. last menstrual period for a male).
0unsupportedUnsupportedThe source system wasn't capable of supporting this element.
0as-textAs TextThe content of the data is represented in the resource narrative.
0errorErrorSome system or workflow process error means that the information is not available.
1  not-a-numberNot a Number (NaN)The numeric value is undefined or unrepresentable due to a floating point processing error.
1  negative-infinityNegative Infinity (NINF)The numeric value is excessively low and unrepresentable due to a floating point processing error.
1  positive-infinityPositive Infinity (PINF)The numeric value is excessively high and unrepresentable due to a floating point processing error.
0not-performedNot PerformedThe value is not available because the observation procedure (test, etc.) was not performed.
0not-permittedNot PermittedThe value is not permitted in this context (e.g. due to profiles, or the base data types).


See the full registry of value sets defined as part of FHIR.

Explanation of the columns that may appear on this page:

LvlA few code lists that FHIR defines are hierarchical - each code is assigned a level. For value sets, levels are mostly used to organize codes for user convenience, but may follow code system hierarchy - see Code System for further information
SourceThe source of the definition of the code (when the value set draws in codes defined elsewhere)
CodeThe code (used as the code in the resource instance). If the code is in italics, this indicates that the code is not selectable ('Abstract')
DisplayThe display (used in the display element of a Coding). If there is no display, implementers should not simply display the code, but map the concept into their application
DefinitionAn explanation of the meaning of the concept
CommentsAdditional notes about how to use the code