Statistical analysis plan with different statistical test if non-normal distribution (id = "example-statistic-model-include-if")

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

<Evidence xmlns="http://hl7.org/fhir">
  <id value="example-statistic-model-include-if"/> 
  <meta> 
    <versionId value="9"/> 
    <lastUpdated value="2025-03-10T14:59:32.227Z"/> 
    <profile value="http://hl7.org/fhir/uv/ebm/StructureDefinition/statistic-model"/> 
  </meta> 
  <extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-wg">
    <valueCode value="cds"/> 
  </extension> 
  <url value="https://fevir.net/resources/Evidence/346428"/> 
  <identifier> 
    <type> 
      <text value="FEvIR Object Identifier"/> 
    </type> 
    <system value="urn:ietf:rfc:3986"/> 
    <value value="https://fevir.net/FOI/346428"/> 
    <assigner> 
      <display value="Computable Publishing LLC"/> 
    </assigner> 
  </identifier> 
  <title value="Example of statistical analysis plan with different statistical test if non-normal
   distribution"/> 
  <status value="active"/> 
  <author> 
    <name value="Brian S. Alper, MD, MSPH"/> 
  </author> 
  <publisher value="HL7 International / Clinical Decision Support"/> 
  <contact> 
    <telecom> 
      <system value="url"/> 
      <value value="http://www.hl7.org/Special/committees/dss"/> 
    </telecom> 
  </contact> 
  <copyright value="https://creativecommons.org/licenses/by-nc-sa/4.0/"/> 
  <description value="This example uses the StatisticModelIncludeIf extension to represent the model
   characteristic of Welch's 2-sample t-test if the data is consistent with a normal
   distribution (based on Shapiro-Wilk test with p-value &gt;= 0.05) and a Wilcoxon
   Mann-Whitney test if not."/> 
  <variableDefinition> 
    <description value="Adults with hypertension"/> 
    <variableRole value="population"/> 
  </variableDefinition> 
  <variableDefinition> 
    <description value="Reversitol vs. Placebo"/> 
    <variableRole value="exposure"/> 
  </variableDefinition> 
  <variableDefinition> 
    <description value="Change in systolic blood pressure from baseline to 3 months"/> 
    <variableRole value="outcome"/> 
  </variableDefinition> 
  <studyDesign> 
    <coding> 
      <system value="https://fevir.net/sevco"/> 
      <code value="SEVCO:01003"/> 
      <display value="randomized assignment"/> 
    </coding> 
  </studyDesign> 
  <statistic> 
    <statisticType> 
      <coding> 
        <system value="https://fevir.net/sevco"/> 
        <code value="STATO:0000457"/> 
        <display value="difference in means"/> 
      </coding> 
    </statisticType> 
    <modelCharacteristic> 
      <extension url="http://hl7.org/fhir/StructureDefinition/statistic-model-include-if">
        <extension url="attribute">
          <valueCodeableConcept> 
            <text value="data distribution"/> 
          </valueCodeableConcept> 
        </extension> 
        <extension url="value">
          <valueCodeableConcept> 
            <text value="normal distribution (Shapiro-Wilk test with p-value &gt;= 0.05)"/> 
          </valueCodeableConcept> 
        </extension> 
      </extension> 
      <code> 
        <text value="Welch's 2-sample t-test"/> 
      </code> 
      <intended value="true"/> 
    </modelCharacteristic> 
    <modelCharacteristic> 
      <extension url="http://hl7.org/fhir/StructureDefinition/statistic-model-include-if">
        <extension url="attribute">
          <valueCodeableConcept> 
            <text value="data distribution"/> 
          </valueCodeableConcept> 
        </extension> 
        <extension url="value">
          <valueCodeableConcept> 
            <text value="not consistent with normal distribution (Shapiro-Wilk test with p-value &lt; 0.05)"/> 
          </valueCodeableConcept> 
        </extension> 
      </extension> 
      <code> 
        <text value="Wilcoxon Mann-Whitney test"/> 
      </code> 
      <intended value="true"/> 
    </modelCharacteristic> 
  </statistic> 
</Evidence>