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    <status value="generated"/><div xmlns="http://www.w3.org/1999/xhtml"><p class="res-header-id"><b>Generated Narrative: CodeSystem observation-statistics</b></p><a name="observation-statistics"> </a><a name="hcobservation-statistics"> </a><p>This case-sensitive code system <code>http://hl7.org/fhir/observation-statistics</code> defines the following codes:</p><table class="codes"><tr><td style="white-space:nowrap"><b>Code</b></td><td><b>Display</b></td><td><b>Definition</b></td></tr><tr><td style="white-space:nowrap">average<a name="observation-statistics-average"> </a></td><td>Average</td><td><div><p>The <a href="https://en.wikipedia.org/wiki/Arithmetic_mean">mean</a> of N measurements over the stated period</p>
</div></td></tr><tr><td style="white-space:nowrap">maximum<a name="observation-statistics-maximum"> </a></td><td>Maximum</td><td><div><p>The <a href="https://en.wikipedia.org/wiki/Maximal_element">maximum</a> value of N measurements over the stated period</p>
</div></td></tr><tr><td style="white-space:nowrap">minimum<a name="observation-statistics-minimum"> </a></td><td>Minimum</td><td><div><p>The <a href="https://en.wikipedia.org/wiki/Minimal_element">minimum</a> value of N measurements over the stated period</p>
</div></td></tr><tr><td style="white-space:nowrap">count<a name="observation-statistics-count"> </a></td><td>Count</td><td><div><p>The [number] of valid measurements over the stated period that contributed to the other statistical outputs</p>
</div></td></tr><tr><td style="white-space:nowrap">totalcount<a name="observation-statistics-totalcount"> </a></td><td>Total Count</td><td><div><p>The total [number] of valid measurements over the stated period, including observations that were ignored because they did not contain valid result values</p>
</div></td></tr><tr><td style="white-space:nowrap">median<a name="observation-statistics-median"> </a></td><td>Median</td><td><div><p>The <a href="https://en.wikipedia.org/wiki/Median">median</a> of N measurements over the stated period</p>
</div></td></tr><tr><td style="white-space:nowrap">std-dev<a name="observation-statistics-std-dev"> </a></td><td>Standard Deviation</td><td><div><p>The <a href="https://en.wikipedia.org/wiki/Standard_deviation">standard deviation</a> of N measurements over the stated period</p>
</div></td></tr><tr><td style="white-space:nowrap">sum<a name="observation-statistics-sum"> </a></td><td>Sum</td><td><div><p>The <a href="https://en.wikipedia.org/wiki/Summation">sum</a> of N measurements over the stated period</p>
</div></td></tr><tr><td style="white-space:nowrap">variance<a name="observation-statistics-variance"> </a></td><td>Variance</td><td><div><p>The <a href="https://en.wikipedia.org/wiki/Variance">variance</a> of N measurements over the stated period</p>
</div></td></tr><tr><td style="white-space:nowrap">20-percent<a name="observation-statistics-20-percent"> </a></td><td>20th Percentile</td><td><div><p>The 20th <a href="https://en.wikipedia.org/wiki/Percentile">Percentile</a> of N measurements over the stated period</p>
</div></td></tr><tr><td style="white-space:nowrap">80-percent<a name="observation-statistics-80-percent"> </a></td><td>80th Percentile</td><td><div><p>The 80th <a href="https://en.wikipedia.org/wiki/Percentile">Percentile</a> of N measurements over the stated period</p>
</div></td></tr><tr><td style="white-space:nowrap">4-lower<a name="observation-statistics-4-lower"> </a></td><td>Lower Quartile</td><td><div><p>The lower <a href="https://en.wikipedia.org/wiki/Quartile">Quartile</a> Boundary of N measurements over the stated period</p>
</div></td></tr><tr><td style="white-space:nowrap">4-upper<a name="observation-statistics-4-upper"> </a></td><td>Upper Quartile</td><td><div><p>The upper <a href="https://en.wikipedia.org/wiki/Quartile">Quartile</a> Boundary of N measurements over the stated period</p>
</div></td></tr><tr><td style="white-space:nowrap">4-dev<a name="observation-statistics-4-dev"> </a></td><td>Quartile Deviation</td><td><div><p>The difference between the upper and lower <a href="https://en.wikipedia.org/wiki/Quartile">Quartiles</a> 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.</p>
</div></td></tr><tr><td style="white-space:nowrap">5-1<a name="observation-statistics-5-1"> </a></td><td>1st Quintile</td><td><div><p>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</p>
</div></td></tr><tr><td style="white-space:nowrap">5-2<a name="observation-statistics-5-2"> </a></td><td>2nd Quintile</td><td><div><p>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</p>
</div></td></tr><tr><td style="white-space:nowrap">5-3<a name="observation-statistics-5-3"> </a></td><td>3rd Quintile</td><td><div><p>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</p>
</div></td></tr><tr><td style="white-space:nowrap">5-4<a name="observation-statistics-5-4"> </a></td><td>4th Quintile</td><td><div><p>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</p>
</div></td></tr><tr><td style="white-space:nowrap">skew<a name="observation-statistics-skew"> </a></td><td>Skew</td><td><div><p>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: <a href="https://en.wikipedia.org/wiki/Skewness">Wikipedia</a></p>
</div></td></tr><tr><td style="white-space:nowrap">kurtosis<a name="observation-statistics-kurtosis"> </a></td><td>Kurtosis</td><td><div><p>Kurtosis  is a measure of the &quot;tailedness&quot; of the probability distribution of a real-valued random variable.   Source: <a href="https://en.wikipedia.org/wiki/Kurtosis">Wikipedia</a></p>
</div></td></tr><tr><td style="white-space:nowrap">regression<a name="observation-statistics-regression"> </a></td><td>Regression</td><td><div><p>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: <a href="https://en.wikipedia.org/wiki/Simple_linear_regression">Wikipedia</a>  This Statistic code will return both a gradient and an intercept value.</p>
</div></td></tr></table></div>
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  <url value="http://hl7.org/fhir/observation-statistics"/>
  <version value="3.0.2"/>
  <name value="StatisticsCode"/>
  <status value="draft"/>
  <experimental value="false"/>
  <date value="2019-10-23T19:53:00-05:00"/>
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  <description value="The statistical operation parameter -&quot;statistic&quot; -  codes"/>
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  <concept>
    <code value="average"/>
    <display value="Average"/>
    <definition value="The [mean](https://en.wikipedia.org/wiki/Arithmetic_mean) of N measurements over the stated period"/>
  </concept>
  <concept>
    <code value="maximum"/>
    <display value="Maximum"/>
    <definition value="The [maximum](https://en.wikipedia.org/wiki/Maximal_element) value of N measurements over the stated period"/>
  </concept>
  <concept>
    <code value="minimum"/>
    <display value="Minimum"/>
    <definition value="The [minimum](https://en.wikipedia.org/wiki/Minimal_element) value of N measurements over the stated period"/>
  </concept>
  <concept>
    <code value="count"/>
    <display value="Count"/>
    <definition value="The [number] of valid measurements over the stated period that contributed to the other statistical outputs"/>
  </concept>
  <concept>
    <code value="totalcount"/>
    <display value="Total Count"/>
    <definition value="The total [number] of valid measurements over the stated period, including observations that were ignored because they did not contain valid result values"/>
  </concept>
  <concept>
    <code value="median"/>
    <display value="Median"/>
    <definition value="The [median](https://en.wikipedia.org/wiki/Median) of N measurements over the stated period"/>
  </concept>
  <concept>
    <code value="std-dev"/>
    <display value="Standard Deviation"/>
    <definition value="The [standard deviation](https://en.wikipedia.org/wiki/Standard_deviation) of N measurements over the stated period"/>
  </concept>
  <concept>
    <code value="sum"/>
    <display value="Sum"/>
    <definition value="The [sum](https://en.wikipedia.org/wiki/Summation) of N measurements over the stated period"/>
  </concept>
  <concept>
    <code value="variance"/>
    <display value="Variance"/>
    <definition value="The [variance](https://en.wikipedia.org/wiki/Variance) of N measurements over the stated period"/>
  </concept>
  <concept>
    <code value="20-percent"/>
    <display value="20th Percentile"/>
    <definition value="The 20th [Percentile](https://en.wikipedia.org/wiki/Percentile) of N measurements over the stated period"/>
  </concept>
  <concept>
    <code value="80-percent"/>
    <display value="80th Percentile"/>
    <definition value="The 80th [Percentile](https://en.wikipedia.org/wiki/Percentile) of N measurements over the stated period"/>
  </concept>
  <concept>
    <code value="4-lower"/>
    <display value="Lower Quartile"/>
    <definition value="The lower [Quartile](https://en.wikipedia.org/wiki/Quartile) Boundary of N measurements over the stated period"/>
  </concept>
  <concept>
    <code value="4-upper"/>
    <display value="Upper Quartile"/>
    <definition value="The upper [Quartile](https://en.wikipedia.org/wiki/Quartile) Boundary of N measurements over the stated period"/>
  </concept>
  <concept>
    <code value="4-dev"/>
    <display value="Quartile Deviation"/>
    <definition value="The difference between the upper and lower [Quartiles](https://en.wikipedia.org/wiki/Quartile) 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."/>
  </concept>
  <concept>
    <code value="5-1"/>
    <display value="1st Quintile"/>
    <definition value="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"/>
  </concept>
  <concept>
    <code value="5-2"/>
    <display value="2nd Quintile"/>
    <definition value="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"/>
  </concept>
  <concept>
    <code value="5-3"/>
    <display value="3rd Quintile"/>
    <definition value="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"/>
  </concept>
  <concept>
    <code value="5-4"/>
    <display value="4th Quintile"/>
    <definition value="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"/>
  </concept>
  <concept>
    <code value="skew"/>
    <display value="Skew"/>
    <definition value="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)"/>
  </concept>
  <concept>
    <code value="kurtosis"/>
    <display value="Kurtosis"/>
    <definition value="Kurtosis  is a measure of the &quot;tailedness&quot; of the probability distribution of a real-valued random variable.   Source: [Wikipedia](https://en.wikipedia.org/wiki/Kurtosis)"/>
  </concept>
  <concept>
    <code value="regression"/>
    <display value="Regression"/>
    <definition value="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)  This Statistic code will return both a gradient and an intercept value."/>
  </concept>
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