---
type: "example"
title: "CodeSystem Example: codesystem-example"
resource: "CodeSystem"
example: "codesystem-example"
---
# CodeSystem Example: codesystem-example

## Narrative

CodeSystem "ACME Codes for Cholesterol": This is an example code system that includes all the codes for serum cholesterol defined by ACME inc.

Developed by: FHIR project team (example)

Published for testing on 28-Jan 2016

This code system defines all the ACME codes for serum cholesterol:

| **Code** | **Display** | **Definition** |
| --- | --- | --- |
| chol-mmol | SChol (mmol/L) | Serum Cholesterol, in mmol/L |
| chol-mass | SChol (mg/L) | Serum Cholesterol, in mg/L |
| chol | SChol | Serum Cholesterol |

## Example XML



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

<CodeSystem xmlns="http://hl7.org/fhir">
  <id value="example"/>
  <meta>
    
  </meta>
  <text>
    <status value="additional"/>
    <div xmlns="http://www.w3.org/1999/xhtml">
      <p>CodeSystem "ACME Codes for Cholesterol": This is an example code system that includes 
        all the codes for serum cholesterol defined by ACME inc.</p>
      <p>Developed by: FHIR project team (example)</p>
      <p>Published for testing on 28-Jan 2016</p>
      <p>This code system defines all the ACME codes for serum cholesterol:</p>
      <table class="grid">
        <tr>
          <td>
            <b>Code</b>
          </td>
          <td>
            <b>Display</b>
          </td>
          <td>
            <b>Definition</b>
          </td>
        </tr>
        <tr>
          <td>chol-mmol</td>
          <td>SChol (mmol/L)</td>
          <td>Serum Cholesterol, in mmol/L</td>
        </tr>
        <tr>
          <td>chol-mass</td>
          <td>SChol (mg/L)</td>
          <td>Serum Cholesterol, in mg/L</td>
        </tr>
        <tr>
          <td>chol</td>
          <td>SChol</td>
          <td>Serum Cholesterol</td>
        </tr>
      </table>
    </div>
  </text>
  
<!--   
	  for this example, we use a real URI, since this example does have a canonical URL
		at which it's posted. Alternatively, We could have used an OID, or a UUID 

    note that since we give a literal URL here, there's an expectation 
			that accessing that URL will give some form of representation of 
			the full code system, or a pointer about how to get more information. 
	
			This is not an absolute requirement, but it may be enforced by some 
			servers - for instance, the HL7 valueset registry will.   -->
  <url value="http://hl7.org/fhir/CodeSystem/example"/>
<!--   an imaginary identifier. This is a non FHIR identifier - might be used in a 
	  v2 context (though you always need to translate namespaces for v2)   -->
  <identifier>
    <system value="urn:ietf:rfc:3986"/>
    <value value="urn:oid:2.16.840.1.113883.4.642.4.1827"/>
  </identifier>
  <identifier>
    <system value="http://acme.com/identifiers/codesystems"/>
    <value value="internal-cholesterol-inl"/>
  </identifier>
<!--   for version, we are going to simply use the day of publication. This is also 
    arbitrary - whatever is here is what people use to refer to the version. 
    Could also be a UUID too. Note that you should change the identify of the code 
    system, not the version, if existing codes are redefined (e.g. don't do that!)  -->
  <version value="20160128"/>

  <name value="ACMECholCodesBlood"/>
  <title value="ACME Codes for Cholesterol in Serum/Plasma"/>
  <status value="draft"/>
  <experimental value="true"/>
  <date value="2016-01-28"/>
	<publisher value="HL7 International / Terminology Infrastructure"/>
	<contact>
		<telecom>
			<system value="url"/>
			<value value="http://hl7.org/fhir"/>
		</telecom>
	</contact>
	<contact>
		<telecom>
			<system value="url"/>
			<value value="http://www.hl7.org/Special/committees/Vocab/index.cfm"/>
		</telecom>
	</contact>
  <description value="This is an example code system that includes all the ACME codes for serum/plasma cholesterol from v2.36."/>
  
  <!--   it's often unstated - are codes case sensitive or not. And 
       it can be the cause of operational or clinical safety problems. 
       So FHIR requires that it always be specified.   -->
  <caseSensitive value="true"/>
  <content value="complete"/>
  
  <!-- filter: Code Systems can define filters that value sets can 
    use to select sets of codes. Note that value sets can also use
    properties (see, e.g. the valueset-example-supplement example)
    and this is always preferred because anything asserted as a 
    filter in the code system will need custom code to make it work.
    For this reason, filters are generally only defined in high value 
    published code systems (unlike this extremely low value example)  -->
  <filter>
    <code value="acme-plasma"/>
    <description value="An internal filter used to select codes that are only used with plasma"/>
    <operator value="="/>
    <value value="the value of this filter is either 'true' or 'false'"/>    
  </filter>
  
  <!--   
			ACME's defined definitions. Note that these are not 
			*good* definitions - but they are very commonly the kind 
			of definitions that are encountered in production
		  -->
  <concept>
    <code value="chol-mmol"/>
    <display value="SChol (mmol/L)"/>
    <definition value="Serum Cholesterol, in mmol/L"/>
    <designation>
      <use>
        <system value="http://acme.com/config/fhir/codesystems/internal"/>
        <code value="internal-label"/>
      </use>
      <value value="From ACME POC Testing"/>
    </designation>
  </concept>
  <concept>
    <code value="chol-mass"/>
    <display value="SChol (mg/L)"/>
    <definition value="Serum Cholesterol, in mg/L"/>
    <designation>
      <use>
        <system value="http://acme.com/config/fhir/codesystems/internal"/>
        <code value="internal-label"/>
      </use>
      <value value="From Paragon Labs"/>
    </designation>
  </concept>
  <concept>
    <code value="chol"/>
    <display value="SChol"/>
    <definition value="Serum Cholesterol"/>
    <designation>
      <use>
        <system value="http://acme.com/config/fhir/codesystems/internal"/>
        <code value="internal-label"/>
      </use>
      <value value="Obdurate Labs uses this with both kinds of units..."/>
    </designation>
  </concept>
</CodeSystem>
```