---
type: "codesystem"
title: "Definition Method"
codesystem: "definition-method"
---
# Definition Method

- **Official URL**: http://hl7.org/fhir/definition-method
- **Version**: 6.0.0
- **Status**: active
- **Name**: DefinitionMethod
- **Title**: Definition Method
- **Publisher**: HL7 (FHIR Project)
- **Description**: The method used to define, describe, or determine a characteristic value.
- **Case Sensitive**: true
- **Content**: complete

## Concepts

| Code | Display | Definition |
| --- | --- | --- |
| systematic-assessment | Systematic Assessment | Any method of routinely determining whether or not specific outcomes (e.g. adverse events) have occurred, for example through a standard questionnaire, regular investigator assessment, regular laboratory testing, or other method |
| non-systematic-assessment | Non-Systematic Assessment | Any non-systematic method for determining whether or not adverse events have occurred, such as self-reporting by participants or occasional assessment/testing |
| mean | Mean | Aggregated using mean of observed values. |
| median | Median | Aggregated using median of observed values. |
| mean-of-mean | Mean of Means | Aggregated using mean of means (e.g. study mean values). |
| mean-of-median | Mean of Medians | Aggregated using mean of medians (e.g. study median values). |
| median-of-mean | Median of Means | Aggregated using median of means (e.g. study mean values). |
| median-of-median | Median of Medians | Aggregated using median of medians (e.g. study median values). |

## CodeSystem XML



```xml
<?xml version="1.0" encoding="UTF-8"?>

<CodeSystem xmlns="http://hl7.org/fhir">
  <id value="definition-method"/>
  <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-wg">
    <valueCode value="fhir"/>
  </extension>
  <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-standards-status">
    <valueCode value="informative"/>
  </extension>
  <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-fmm">
    <valueInteger value="1"/>
  </extension>
  <url value="http://hl7.org/fhir/definition-method"/>
  <identifier>
    <system value="urn:ietf:rfc:3986"/>
    <value value="urn:oid:2.16.840.1.113883.4.642.4.1953"/>
  </identifier>
  <version value="6.0.0"/>
  <name value="DefinitionMethod"/>
  <title value="Definition Method"/>
  <status value="active"/>
  <experimental value="false"/>
  <date value="2020-12-28T16:55:11+11:00"/>
  <publisher value="HL7 (FHIR Project)"/>
  <contact>
    <telecom>
      <system value="url"/>
      <value value="http://hl7.org/fhir"/>
    </telecom>
    <telecom>
      <system value="email"/>
      <value value="fhir@lists.hl7.org"/>
    </telecom>
  </contact>
  <description value="The method used to define, describe, or determine a characteristic value."/>
  <caseSensitive value="true"/>
  <valueSet value="http://hl7.org/fhir/ValueSet/definition-method"/>
  <content value="complete"/>
  <concept>
    <code value="systematic-assessment"/>
    <display value="Systematic Assessment"/>
    <definition value="Any method of routinely determining whether or not specific outcomes (e.g. adverse events) have occurred, for example through a standard questionnaire, regular investigator assessment, regular laboratory testing, or other method"/>
  </concept>
  <concept>
    <code value="non-systematic-assessment"/>
    <display value="Non-Systematic Assessment"/>
    <definition value="Any non-systematic method for determining whether or not adverse events have occurred, such as self-reporting by participants or occasional assessment/testing"/>
  </concept>
  <concept>
    <code value="mean"/>
    <display value="Mean"/>
    <definition value="Aggregated using mean of observed values."/>
  </concept>
  <concept>
    <code value="median"/>
    <display value="Median"/>
    <definition value="Aggregated using median of observed values."/>
  </concept>
  <concept>
    <code value="mean-of-mean"/>
    <display value="Mean of Means"/>
    <definition value="Aggregated using mean of means (e.g. study mean values)."/>
  </concept>
  <concept>
    <code value="mean-of-median"/>
    <display value="Mean of Medians"/>
    <definition value="Aggregated using mean of medians (e.g. study median values)."/>
  </concept>
  <concept>
    <code value="median-of-mean"/>
    <display value="Median of Means"/>
    <definition value="Aggregated using median of means (e.g. study mean values)."/>
  </concept>
  <concept>
    <code value="median-of-median"/>
    <display value="Median of Medians"/>
    <definition value="Aggregated using median of medians (e.g. study median values)."/>
  </concept>
</CodeSystem>
```