Release 4 FHIR CI-Build

This page is part of the Continuous Integration Build of FHIR Specification (v4.0.1: R4 - Mixed Normative and STU ) in it's permanent home (it will always (will be available incorrect/inconsistent at this URL). The current version which supercedes this version is 5.0.0 . For a full list of available versions, see times).
See the Directory of published versions icon . Page versions: R5 R4B R4 R3

Using Codes Code Systems Value Sets Concept Maps Identifier Systems

4.4.1.624 4.4.1.683 Value Set ValueSet http://hl7.org/fhir/ValueSet/observation-statistics

  Maturity Level : 0
Responsible Owner: Orders and Observations icon Work Group Informative Use Context : Any Country: World
This is a value set defined by the FHIR project. Summary Committee:
Official URL : Title: http://hl7.org/fhir/ValueSet/observation-statistics StatisticsCode Definition: The statistical operation parameter -"statistic" codes. Version : 6.0.0-ballot3
active as of 2025-11-24 Orders and Observations Computable Name : StatisticsCode Work Group
OID: Flags : 2.16.840.1.113883.4.642.3.405 (for OID based terminology systems) Source Resource XML / JSON : 2.16.840.1.113883.4.642.3.405

This value set is used in the following places:

4.4.1.624.1 4.4.1.683.1 Definition

Description Needed Here

4.4.1.683.2 Content Logical Definition

This value set includes codes from the following code systems:

Generated Narrative: ValueSet observation-statistics

Last updated: 2025-11-24T20:46:00.1Z

 

4.4.1.624.2 4.4.1.683.3 Expansion

This expansion generated 01 24 Nov 2019 2025

ValueSet This value set contains 21 concepts

Expansion performed internally based on http://terminology.hl7.org/CodeSystem/observation-statistics version 4.0.1 All codes from system http://terminology.hl7.org/CodeSystem/observation-statistics codesystem Statistics Code v6.0.0-ballot3 (CodeSystem)

This value set contains 21 concepts

System Code Display Definition
http://hl7.org/fhir/observation-statistics    average Average

The [mean](https://en.wikipedia.org/wiki/Arithmetic_mean) mean icon of N measurements over the stated period.

http://hl7.org/fhir/observation-statistics    maximum Maximum

The [maximum](https://en.wikipedia.org/wiki/Maximal_element) maximum icon value of N measurements over the stated period.

http://hl7.org/fhir/observation-statistics    minimum Minimum

The [minimum](https://en.wikipedia.org/wiki/Minimal_element) minimum icon value of N measurements over the stated period.

http://hl7.org/fhir/observation-statistics    count Count

The [number] of valid measurements over the stated period that contributed to the other statistical outputs.

http://hl7.org/fhir/observation-statistics    total-count Total Count

The total [number] of valid measurements over the stated period, including observations that were ignored because they did not contain valid result values.

http://hl7.org/fhir/observation-statistics    median Median

The [median](https://en.wikipedia.org/wiki/Median) median icon of N measurements over the stated period.

http://hl7.org/fhir/observation-statistics    std-dev Standard Deviation

The [standard deviation](https://en.wikipedia.org/wiki/Standard_deviation) standard deviation icon of N measurements over the stated period.

http://hl7.org/fhir/observation-statistics    sum Sum

The [sum](https://en.wikipedia.org/wiki/Summation) sum icon of N measurements over the stated period.

http://hl7.org/fhir/observation-statistics    variance Variance

The [variance](https://en.wikipedia.org/wiki/Variance) variance icon of N measurements over the stated period.

http://hl7.org/fhir/observation-statistics    20-percent 20th Percentile

The 20th [Percentile](https://en.wikipedia.org/wiki/Percentile) Percentile icon of N measurements over the stated period.

http://hl7.org/fhir/observation-statistics    80-percent 80th Percentile

The 80th [Percentile](https://en.wikipedia.org/wiki/Percentile) Percentile icon of N measurements over the stated period.

http://hl7.org/fhir/observation-statistics    4-lower Lower Quartile

The lower [Quartile](https://en.wikipedia.org/wiki/Quartile) Quartile icon Boundary of N measurements over the stated period.

http://hl7.org/fhir/observation-statistics    4-upper Upper Quartile

The upper [Quartile](https://en.wikipedia.org/wiki/Quartile) Quartile icon Boundary of N measurements over the stated period.

http://hl7.org/fhir/observation-statistics    4-dev Quartile Deviation

The difference between the upper and lower [Quartiles](https://en.wikipedia.org/wiki/Quartile) Quartiles icon is called the Interquartile range. (IQR = Q3-Q1) Quartile deviation or Semi-interquartile range is one-half the difference between the first and the third quartiles.

http://hl7.org/fhir/observation-statistics    5-1 1st Quintile

The lowest of four values that divide the N measurements into a frequency distribution of five classes with each containing one fifth of the total population.

http://hl7.org/fhir/observation-statistics    5-2 2nd Quintile

The second of four values that divide the N measurements into a frequency distribution of five classes with each containing one fifth of the total population.

http://hl7.org/fhir/observation-statistics    5-3 3rd Quintile

The third of four values that divide the N measurements into a frequency distribution of five classes with each containing one fifth of the total population.

http://hl7.org/fhir/observation-statistics    5-4 4th Quintile

The fourth of four values that divide the N measurements into a frequency distribution of five classes with each containing one fifth of the total population.

http://hl7.org/fhir/observation-statistics    skew Skew

Skewness is a measure of the asymmetry of the probability distribution of a real-valued random variable about its mean. The skewness value can be positive or negative, or even undefined. Source: [Wikipedia](https://en.wikipedia.org/wiki/Skewness). Wikipedia icon.
http://hl7.org/fhir/observation-statistics    kurtosis Kurtosis

Kurtosis is a measure of the "tailedness" of the probability distribution of a real-valued random variable. Source: [Wikipedia](https://en.wikipedia.org/wiki/Kurtosis). Wikipedia icon.
http://hl7.org/fhir/observation-statistics    regression Regression

Linear regression is an approach for modeling two-dimensional sample points with one independent variable and one dependent variable (conventionally, the x and y coordinates in a Cartesian coordinate system) and finds a linear function (a non-vertical straight line) that, as accurately as possible, predicts the dependent variable values as a function of the independent variables. Source: [Wikipedia](https://en.wikipedia.org/wiki/Simple_linear_regression) Wikipedia icon This Statistic code will return both a gradient and an intercept value.

 

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

Explanation of the columns that may appear on this page:

Lvl A 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
Source The source of the definition of the code (when the value set draws in codes defined elsewhere)
Code The code (used as the code in the resource instance). If the code is in italics, this indicates that the code is not selectable ('Abstract')
Display The 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
Definition An explanation of the meaning of the concept
Comments Additional notes about how to use the code