This page is part of the HL7 Terminology (v1.0.0: Release) based on FHIR R4. The current version which supercedes this version is 2.1.0. For a full list of available versions, see the Directory of published versions

**Source view**

{ "resourceType" : "CodeSystem", "id" : "observation-statistics", "meta" : { "lastUpdated" : "2020-04-09T21:10:28.568+00:00" }, "text" : { "status" : "generated", "div" : "<div xmlns=\"http://www.w3.org/1999/xhtml\">\n \n <h2>StatisticsCode</h2>\n \n <div>\n \n <p>The statistical operation parameter -"statistic" codes.</p>\n\n \n </div>\n \n <p>This code system http://terminology.hl7.org/CodeSystem/observation-statistics defines the following codes:</p>\n \n <table class=\"codes\">\n \n <tr>\n \n <td style=\"white-space:nowrap\">\n \n <b>Code</b>\n \n </td>\n \n <td>\n \n <b>Display</b>\n \n </td>\n \n <td>\n \n <b>Definition</b>\n \n </td>\n \n </tr>\n \n <tr>\n \n <td style=\"white-space:nowrap\">average\n \n <a name=\"observation-statistics-average\"> </a>\n \n </td>\n \n <td>Average</td>\n \n <td>The [mean](https://en.wikipedia.org/wiki/Arithmetic_mean) of N measurements over the stated period.</td>\n \n </tr>\n \n <tr>\n \n <td style=\"white-space:nowrap\">maximum\n \n <a name=\"observation-statistics-maximum\"> </a>\n \n </td>\n \n <td>Maximum</td>\n \n <td>The [maximum](https://en.wikipedia.org/wiki/Maximal_element) value of N measurements over the stated period.</td>\n \n </tr>\n \n <tr>\n \n <td style=\"white-space:nowrap\">minimum\n \n <a name=\"observation-statistics-minimum\"> </a>\n \n </td>\n \n <td>Minimum</td>\n \n <td>The [minimum](https://en.wikipedia.org/wiki/Minimal_element) value of N measurements over the stated period.</td>\n \n </tr>\n \n <tr>\n \n <td style=\"white-space:nowrap\">count\n \n <a name=\"observation-statistics-count\"> </a>\n \n </td>\n \n <td>Count</td>\n \n <td>The [number] of valid measurements over the stated period that contributed to the other statistical outputs.</td>\n \n </tr>\n \n <tr>\n \n <td style=\"white-space:nowrap\">total-count\n \n <a name=\"observation-statistics-total-count\"> </a>\n \n </td>\n \n <td>Total Count</td>\n \n <td>The total [number] of valid measurements over the stated period, including observations that were ignored because they did not contain valid result values.</td>\n \n </tr>\n \n <tr>\n \n <td style=\"white-space:nowrap\">median\n \n <a name=\"observation-statistics-median\"> </a>\n \n </td>\n \n <td>Median</td>\n \n <td>The [median](https://en.wikipedia.org/wiki/Median) of N measurements over the stated period.</td>\n \n </tr>\n \n <tr>\n \n <td style=\"white-space:nowrap\">std-dev\n \n <a name=\"observation-statistics-std-dev\"> </a>\n \n </td>\n \n <td>Standard Deviation</td>\n \n <td>The [standard deviation](https://en.wikipedia.org/wiki/Standard_deviation) of N measurements over the stated period.</td>\n \n </tr>\n \n <tr>\n \n <td style=\"white-space:nowrap\">sum\n \n <a name=\"observation-statistics-sum\"> </a>\n \n </td>\n \n <td>Sum</td>\n \n <td>The [sum](https://en.wikipedia.org/wiki/Summation) of N measurements over the stated period.</td>\n \n </tr>\n \n <tr>\n \n <td style=\"white-space:nowrap\">variance\n \n <a name=\"observation-statistics-variance\"> </a>\n \n </td>\n \n <td>Variance</td>\n \n <td>The [variance](https://en.wikipedia.org/wiki/Variance) of N measurements over the stated period.</td>\n \n </tr>\n \n <tr>\n \n <td style=\"white-space:nowrap\">20-percent\n \n <a name=\"observation-statistics-20-percent\"> </a>\n \n </td>\n \n <td>20th Percentile</td>\n \n <td>The 20th [Percentile](https://en.wikipedia.org/wiki/Percentile) of N measurements over the stated period.</td>\n \n </tr>\n \n <tr>\n \n <td style=\"white-space:nowrap\">80-percent\n \n <a name=\"observation-statistics-80-percent\"> </a>\n \n </td>\n \n <td>80th Percentile</td>\n \n <td>The 80th [Percentile](https://en.wikipedia.org/wiki/Percentile) of N measurements over the stated period.</td>\n \n </tr>\n \n <tr>\n \n <td style=\"white-space:nowrap\">4-lower\n \n <a name=\"observation-statistics-4-lower\"> </a>\n \n </td>\n \n <td>Lower Quartile</td>\n \n <td>The lower [Quartile](https://en.wikipedia.org/wiki/Quartile) Boundary of N measurements over the stated period.</td>\n \n </tr>\n \n <tr>\n \n <td style=\"white-space:nowrap\">4-upper\n \n <a name=\"observation-statistics-4-upper\"> </a>\n \n </td>\n \n <td>Upper Quartile</td>\n \n <td>The upper [Quartile](https://en.wikipedia.org/wiki/Quartile) Boundary of N measurements over the stated period.</td>\n \n </tr>\n \n <tr>\n \n <td style=\"white-space:nowrap\">4-dev\n \n <a name=\"observation-statistics-4-dev\"> </a>\n \n </td>\n \n <td>Quartile Deviation</td>\n \n <td>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.</td>\n \n </tr>\n \n <tr>\n \n <td style=\"white-space:nowrap\">5-1\n \n <a name=\"observation-statistics-5-1\"> </a>\n \n </td>\n \n <td>1st Quintile</td>\n \n <td>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.</td>\n \n </tr>\n \n <tr>\n \n <td style=\"white-space:nowrap\">5-2\n \n <a name=\"observation-statistics-5-2\"> </a>\n \n </td>\n \n <td>2nd Quintile</td>\n \n <td>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.</td>\n \n </tr>\n \n <tr>\n \n <td style=\"white-space:nowrap\">5-3\n \n <a name=\"observation-statistics-5-3\"> </a>\n \n </td>\n \n <td>3rd Quintile</td>\n \n <td>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.</td>\n \n </tr>\n \n <tr>\n \n <td style=\"white-space:nowrap\">5-4\n \n <a name=\"observation-statistics-5-4\"> </a>\n \n </td>\n \n <td>4th Quintile</td>\n \n <td>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.</td>\n \n </tr>\n \n <tr>\n \n <td style=\"white-space:nowrap\">skew\n \n <a name=\"observation-statistics-skew\"> </a>\n \n </td>\n \n <td>Skew</td>\n \n <td>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).</td>\n \n </tr>\n \n <tr>\n \n <td style=\"white-space:nowrap\">kurtosis\n \n <a name=\"observation-statistics-kurtosis\"> </a>\n \n </td>\n \n <td>Kurtosis</td>\n \n <td>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).</td>\n \n </tr>\n \n <tr>\n \n <td style=\"white-space:nowrap\">regression\n \n <a name=\"observation-statistics-regression\"> </a>\n \n </td>\n \n <td>Regression</td>\n \n <td>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.</td>\n \n </tr>\n \n </table>\n \n </div>" }, "url" : "http://terminology.hl7.org/CodeSystem/observation-statistics", "identifier" : [ { "system" : "urn:ietf:rfc:3986", "value" : "urn:oid:2.16.840.1.113883.4.642.1.1126" } ], "version" : "4.2.0", "name" : "StatisticsCode", "title" : "StatisticsCode", "status" : "draft", "experimental" : false, "date" : "2020-04-09T21:10:28+00:00", "publisher" : "HL7 (FHIR Project)", "contact" : [ { "telecom" : [ { "system" : "url", "value" : "http://hl7.org/fhir" }, { "system" : "email", "value" : "fhir@lists.hl7.org" } ] } ], "description" : "The statistical operation parameter -\"statistic\" codes.", "caseSensitive" : true, "valueSet" : "http://terminology.hl7.org/ValueSet/observation-statistics", "content" : "complete", "concept" : [ { "code" : "average", "display" : "Average", "definition" : "The [mean](https://en.wikipedia.org/wiki/Arithmetic_mean) of N measurements over the stated period." }, { "code" : "maximum", "display" : "Maximum", "definition" : "The [maximum](https://en.wikipedia.org/wiki/Maximal_element) value of N measurements over the stated period." }, { "code" : "minimum", "display" : "Minimum", "definition" : "The [minimum](https://en.wikipedia.org/wiki/Minimal_element) value of N measurements over the stated period." }, { "code" : "count", "display" : "Count", "definition" : "The [number] of valid measurements over the stated period that contributed to the other statistical outputs." }, { "code" : "total-count", "display" : "Total Count", "definition" : "The total [number] of valid measurements over the stated period, including observations that were ignored because they did not contain valid result values." }, { "code" : "median", "display" : "Median", "definition" : "The [median](https://en.wikipedia.org/wiki/Median) of N measurements over the stated period." }, { "code" : "std-dev", "display" : "Standard Deviation", "definition" : "The [standard deviation](https://en.wikipedia.org/wiki/Standard_deviation) of N measurements over the stated period." }, { "code" : "sum", "display" : "Sum", "definition" : "The [sum](https://en.wikipedia.org/wiki/Summation) of N measurements over the stated period." }, { "code" : "variance", "display" : "Variance", "definition" : "The [variance](https://en.wikipedia.org/wiki/Variance) of N measurements over the stated period." }, { "code" : "20-percent", "display" : "20th Percentile", "definition" : "The 20th [Percentile](https://en.wikipedia.org/wiki/Percentile) of N measurements over the stated period." }, { "code" : "80-percent", "display" : "80th Percentile", "definition" : "The 80th [Percentile](https://en.wikipedia.org/wiki/Percentile) of N measurements over the stated period." }, { "code" : "4-lower", "display" : "Lower Quartile", "definition" : "The lower [Quartile](https://en.wikipedia.org/wiki/Quartile) Boundary of N measurements over the stated period." }, { "code" : "4-upper", "display" : "Upper Quartile", "definition" : "The upper [Quartile](https://en.wikipedia.org/wiki/Quartile) Boundary of N measurements over the stated period." }, { "code" : "4-dev", "display" : "Quartile Deviation", "definition" : "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." }, { "code" : "5-1", "display" : "1st Quintile", "definition" : "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." }, { "code" : "5-2", "display" : "2nd Quintile", "definition" : "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." }, { "code" : "5-3", "display" : "3rd Quintile", "definition" : "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." }, { "code" : "5-4", "display" : "4th Quintile", "definition" : "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." }, { "code" : "skew", "display" : "Skew", "definition" : "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)." }, { "code" : "kurtosis", "display" : "Kurtosis", "definition" : "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)." }, { "code" : "regression", "display" : "Regression", "definition" : "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." } ] }