Evidence Based Medicine on FHIR Implementation Guide
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Evidence Based Medicine on FHIR Implementation Guide, published by HL7 International / Clinical Decision Support. This guide is not an authorized publication; it is the continuous build for version 1.0.0-ballot built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/HL7/ebm/ and changes regularly. See the Directory of published versions

: ComparativeEvidence: Mean difference in HbA1c effect of bariatric surgery in 2016 meta-analysis - XML Representation

Active as of 2022-05-28

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    <lastUpdated value="2023-12-08T16:30:32.804Z"/>
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    <profile
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  </meta>
  <text>
    <status value="extensions"/>
    <div xmlns="http://www.w3.org/1999/xhtml"><p><b>Generated Narrative: Evidence</b><a name="33244"> </a><a name="hc33244"> </a></p><div style="display: inline-block; background-color: #d9e0e7; padding: 6px; margin: 4px; border: 1px solid #8da1b4; border-radius: 5px; line-height: 60%"><p style="margin-bottom: 0px">ResourceEvidence &quot;33244&quot; Version &quot;36&quot; Updated &quot;2023-12-08 16:30:32+0000&quot; </p><p style="margin-bottom: 0px">Profiles: <a href="StructureDefinition-comparative-evidence.html">ComparativeEvidence</a>, <a href="StructureDefinition-evidence-synthesis-evidence.html">EvidenceSynthesisEvidence</a></p></div><p><b>url</b>: <code>https://fevir.net/resources/Evidence/33244</code></p><p><b>identifier</b>: FEvIR Object Identifier/33244</p><p><b>version</b>: 1.0.0-ballot</p><p><b>name</b>: MeanDiffA1c2016metaAnalysis</p><p><b>title</b>: ComparativeEvidence: Mean difference in HbA1c effect of bariatric surgery in 2016 meta-analysis</p><p><b>status</b>: active</p><p><b>date</b>: 2022-05-28 12:01:55+0000</p><p><b>publisher</b>: HL7 International / Clinical Decision Support</p><p><b>contact</b>: HL7 International / Clinical Decision Support: <a href="http://www.hl7.org/Special/committees/dss">http://www.hl7.org/Special/committees/dss</a></p><p><b>author</b>: Brian S. Alper: </p><h3>UseContexts</h3><table class="grid"><tr><td style="display: none">-</td><td><b>Code</b></td><td><b>Value[x]</b></td></tr><tr><td style="display: none">*</td><td>Evidence Communication (Details: Evidence Based Medicine on FHIR Implementation Guide Code System code evidence-communication = 'Evidence Communication', stated as 'Evidence Communication')</td><td>ComparativeEvidence <span style="background: LightGoldenRodYellow; margin: 4px; border: 1px solid khaki"> (<a href="CodeSystem-179423.html">Evidence Based Medicine on FHIR Implementation Guide Code System</a>#ComparativeEvidence)</span></td></tr><tr><td style="display: none">*</td><td>Evidence Communication (Details: Evidence Based Medicine on FHIR Implementation Guide Code System code evidence-communication = 'Evidence Communication', stated as 'Evidence Communication')</td><td>EvidenceSynthesisEvidence <span style="background: LightGoldenRodYellow; margin: 4px; border: 1px solid khaki"> (<a href="CodeSystem-179423.html">Evidence Based Medicine on FHIR Implementation Guide Code System</a>#EvidenceSynthesisEvidence)</span></td></tr></table><p><b>copyright</b>: https://creativecommons.org/licenses/by-nc-sa/4.0/</p><blockquote><p><b>relatedArtifact</b></p><p><b>type</b>: derived-from</p><p><b>label</b>: data source</p><p><b>display</b>: Figure 2C</p><p><b>citation</b>: Metabolic Surgery in the Treatment Algorithm for Type 2 Diabetes: A Joint Statement by International Diabetes Organizations [Journal Article]. Contributors: Francesco Rubino, David M Nathan, Robert H Eckel, Philip R Schauer, K George M M Alberti, Paul Z Zimmet, Stefano Del Prato, Linong Ji, Shaukat M Sadikot, William H Herman, Stephanie A Amiel, Lee M Kaplan, Gaspar Taroncher-Oldenburg, David E Cummings, Delegates of the 2nd Diabetes Surgery Summit. In: Diabetes care, PMID 27222544. Published June 2016. Available at: https://pubmed.ncbi.nlm.nih.gov/27222544/.</p><blockquote><p><b>document</b></p></blockquote></blockquote><blockquote><p><b>relatedArtifact</b></p><p><b>type</b>: supported-with</p><p><b>classifier</b>: Citation Resource for the original article <span style="background: LightGoldenRodYellow; margin: 4px; border: 1px solid khaki"> ()</span></p><p><b>display</b>: Citation Resource for Metabolic Surgery in the Treatment Algorithm for Type 2 Diabetes: A Joint Statement by International Diabetes Organizations - PMID 27222544</p><p><b>resourceReference</b>: <a href="Citation-33089.html">Citation/33089: Metabolic Surgery in the Treatment Algorithm for Type 2 Diabetes: A Joint Statement by International Diabetes Organizations-Citation</a></p></blockquote><blockquote><p><b>relatedArtifact</b></p><p><b>type</b>: cite-as</p><p><b>citation</b>: ComparativeEvidence: Mean difference in HbA1c effect of bariatric surgery in 2016 meta-analysis [Evidence]. Contributors: Brian S. Alper [Authors/Creators]. In: Fast Evidence Interoperability Resources (FEvIR) Platform, FOI 33244. Revised 2022-05-28. Available at: https://fevir.net/resources/Evidence/33244. Computable resource at: https://fevir.net/resources/Evidence/33244.</p></blockquote><p><b>description</b>: effect estimate for differences in mean HbA1c at study end point between Surgery and Medical/Lifestyle groups -1.14% (95% CI -1.57% to -0.71%) in meta-analysis of 15 trials with 1,067 participants</p><p><b>note</b>: summary derived from Figure 2C as data not reported in the text</p><blockquote><p><b>variableDefinition</b></p><p><b>VariableDefinitionVariableRoleCode</b>: population</p><p><b>description</b>: Patients with type 2 diabetes *NOTE: note.text is used artificially to support the EBMonFHIR Implementation Guide and the following content would more properly be found in a note.text element:* The observed element can reference a Group Resource that represents an actual group of studies included and has a quantity.  The quantity would be the number of members (number of studies), and the characteristic can be code 'Member of' and valueReference EvidenceList with an EvidenceList that can reference the Evidence Resources representing the individual study results. This meta-analysis included 15 studies. The intended element (if desired) can reference a Group Resource that expresses the population of studies intended for evidence application through structured characteristics. The structured characteristics could be used to express the SR eligibility criteria for participants (i.e. included studies). The included trials included patients with T2D, including mainly individuals with BMI ≥35 kg/m2 (the most commonly used threshold for traditional bariatric surgery) as well as some patients with BMI &lt;35 kg/m2 (range 25–35 kg/m2).</p><p><b>note</b>: population</p><p><b>variableRole</b>: Use extension:variableRoleCode instead. <span style="background: LightGoldenRodYellow; margin: 4px; border: 1px solid khaki"> (<a href="http://terminology.hl7.org/5.5.0/CodeSystem-variable-role.html">EvidenceVariableRole</a>#population &quot;population&quot;)</span></p><p><b>observed</b>: <a href="Group-33395.html">Group/33395: MetaanalysisStudyGroup: Study results included in Mean difference in HbA1c effect of bariatric surgery in 2016 meta-analysis</a></p><p><b>intended</b>: <a href="Group-175766.html">Group/175766: MetaanalysisEligibilityCriteria: Mean difference in HbA1c effect of bariatric surgery in type 2 diabetes and elevated BMI in 2016 meta-analysis</a> &quot;MetaanalysisEligibilityCriteria_Mean_difference_in_HbA1c_effect_of_bariatric_surgery_in_type_2_diabetes_and_elevated_BMI_in_2016_meta_analysis&quot;</p></blockquote><blockquote><p><b>variableDefinition</b></p><p><b>VariableDefinitionVariableRoleCode</b>: exposure</p><p><b>VariableDefinitionComparatorCategory</b>: no bariatric surgery</p><p><b>description</b>: Any of 4 bariatric surgery procedures (Roux-en-Y Gastric Bypass, Vertical Sleeve Gastrectomy, Laparoscopic Adjustable Gastric banding, Biliopancreatic Diversion) vs. Medical/lifestyle interventions *NOTE: note.text is used artificially to support the EBMonFHIR Implementation Guide and the following content would more properly be found in a note.text element:* As the control group (observed reference exposure) was defined differently in each trial, the intended reference exposure is described as the absence of the intended exposure (Bariatric Surgery).</p><p><b>note</b>: exposure</p><p><b>variableRole</b>: Use extension:variableRoleCode instead. <span style="background: LightGoldenRodYellow; margin: 4px; border: 1px solid khaki"> (<a href="http://terminology.hl7.org/5.5.0/CodeSystem-variable-role.html">EvidenceVariableRole</a>#exposure &quot;exposure&quot;)</span></p><p><b>intended</b>: <a href="EvidenceVariable-172427.html">EvidenceVariable/172427: GroupAssignment: Bariatric Surgery vs. no bariatric surgery</a> &quot;GroupAssignment_Bariatric_Surgery_vs_no_bariatric_surgery&quot;</p></blockquote><blockquote><p><b>variableDefinition</b></p><p><b>VariableDefinitionVariableRoleCode</b>: outcome</p><p><b>description</b>: Mean difference in HbA1c between Surgery and Medical/Lifestyle groups at end of follow-up for HbA1c end point</p><p><b>note</b>: outcome</p><p><b>variableRole</b>: Use extension:variableRoleCode instead. <span style="background: LightGoldenRodYellow; margin: 4px; border: 1px solid khaki"> (<a href="http://terminology.hl7.org/5.5.0/CodeSystem-variable-role.html">EvidenceVariableRole</a>#measuredVariable &quot;measured variable&quot;)</span></p><p><b>observed</b>: <a href="EvidenceVariable-46025.html">EvidenceVariable/46025: OutcomeVariable: Mean difference in HbA1c between Surgery and Medical/Lifestyle groups at end of follow-up for HbA1c end point</a> &quot;OutcomeVariable_Mean_difference_in_HbA1c_between_Surgery_and_Medical_Lifestyle_groups_at_end_of_follow_up&quot;</p></blockquote><p><b>synthesisType</b>: summary data meta-analysis <span style="background: LightGoldenRodYellow; margin: 4px; border: 1px solid khaki"> (StatisticSynthesisType[3.1.0]#std-MA)</span></p><p><b>studyDesign</b>: randomized assignment <span style="background: LightGoldenRodYellow; margin: 4px; border: 1px solid khaki"> (<a href="CodeSystem-181513.html">Scientific Evidence Code System (SEVCO) -- EXAMPLE VERSION for EBMonFHIR Implementation Guide</a>#SEVCO:01003)</span></p><blockquote><p><b>statistic</b></p><p><b>description</b>: mean difference in HbA1c -1.14% (95% CI -1.57% to -0.71%)</p><p><b>note</b>: random-effects model, heterogeneity tau-squared 0.63; chi-squared 200.88, df 14 (p &lt; 0.00001), I-squared 93%, test for overall effect z = 5.20 (p &lt; 0.00001)</p><p><b>statisticType</b>: A mean of values in which each value is the subtraction of one quantity from another. <span style="background: LightGoldenRodYellow; margin: 4px; border: 1px solid khaki"> (<a href="http://terminology.hl7.org/5.5.0/CodeSystem-statistic-type.html">StatisticStatisticType</a>#0000457 &quot;Mean Difference&quot;)</span></p><p><b>quantity</b>: -1.14 %<span style="background: LightGoldenRodYellow"> (Details: UCUM code % = '%')</span></p><h3>SampleSizes</h3><table class="grid"><tr><td style="display: none">-</td><td><b>Description</b></td><td><b>NumberOfStudies</b></td><td><b>NumberOfParticipants</b></td><td><b>KnownDataCount</b></td></tr><tr><td style="display: none">*</td><td>15 studies with 1067 participants contributing to analysis</td><td>15</td><td>0</td><td>1067</td></tr></table><blockquote><p><b>attributeEstimate</b></p><p><b>description</b>: 95% CI -1.57% to -0.71%</p><p><b>type</b>: Confidence interval <span style="background: LightGoldenRodYellow; margin: 4px; border: 1px solid khaki"> (<a href="http://terminology.hl7.org/5.5.0/CodeSystem-attribute-estimate-type.html">StatisticAttribute Estimate Type</a>#C53324)</span></p><p><b>level</b>: 0.95</p><p><b>range</b>: -1.57--0.71 %</p></blockquote><blockquote><p><b>attributeEstimate</b></p><p><b>description</b>: z = 5.20</p><p><b>type</b>: Z-score <span style="background: LightGoldenRodYellow; margin: 4px; border: 1px solid khaki"> (<a href="CodeSystem-179423.html">Evidence Based Medicine on FHIR Implementation Guide Code System</a>#defined-in-text &quot;Defined in text&quot;)</span></p><p><b>quantity</b>: 5.2</p></blockquote><blockquote><p><b>attributeEstimate</b></p><p><b>description</b>: p &lt; 0.00001</p><p><b>type</b>: P-value <span style="background: LightGoldenRodYellow; margin: 4px; border: 1px solid khaki"> (<a href="http://terminology.hl7.org/5.5.0/CodeSystem-attribute-estimate-type.html">StatisticAttribute Estimate Type</a>#C44185)</span></p><p><b>quantity</b>: &lt;0.00001</p></blockquote><blockquote><p><b>attributeEstimate</b></p><p><b>description</b>: Tau squared = 0.63</p><p><b>type</b>: Tau squared <span style="background: LightGoldenRodYellow; margin: 4px; border: 1px solid khaki"> (<a href="http://terminology.hl7.org/5.5.0/CodeSystem-attribute-estimate-type.html">StatisticAttribute Estimate Type</a>#0000421)</span></p><p><b>quantity</b>: 0.63</p></blockquote><blockquote><p><b>attributeEstimate</b></p><p><b>description</b>: Chi square for homogeneity 200.88, df 14 (p &lt; 0.00001)</p><p><b>type</b>: Chi square for homogeneity <span style="background: LightGoldenRodYellow; margin: 4px; border: 1px solid khaki"> (<a href="CodeSystem-179423.html">Evidence Based Medicine on FHIR Implementation Guide Code System</a>#defined-in-text &quot;Defined in text&quot;)</span></p><p><b>quantity</b>: 200.88</p><h3>AttributeEstimates</h3><table class="grid"><tr><td style="display: none">-</td><td><b>Description</b></td><td><b>Type</b></td><td><b>Quantity</b></td></tr><tr><td style="display: none">*</td><td>degrees of freedom (df) = 14</td><td>Degrees of Freedom <span style="background: LightGoldenRodYellow; margin: 4px; border: 1px solid khaki"> (<a href="CodeSystem-179423.html">Evidence Based Medicine on FHIR Implementation Guide Code System</a>#defined-in-text &quot;Defined in text&quot;)</span></td><td>14</td></tr><tr><td style="display: none">*</td><td>p &lt; 0.00001</td><td>P-value <span style="background: LightGoldenRodYellow; margin: 4px; border: 1px solid khaki"> (<a href="http://terminology.hl7.org/5.5.0/CodeSystem-attribute-estimate-type.html">StatisticAttribute Estimate Type</a>#C44185)</span></td><td>&lt;0.00001</td></tr></table></blockquote><blockquote><p><b>attributeEstimate</b></p><p><b>description</b>: I-squared = 93%</p><p><b>type</b>: I-squared <span style="background: LightGoldenRodYellow; margin: 4px; border: 1px solid khaki"> (<a href="http://terminology.hl7.org/5.5.0/CodeSystem-attribute-estimate-type.html">StatisticAttribute Estimate Type</a>#0000420)</span></p><p><b>quantity</b>: 93 %<span style="background: LightGoldenRodYellow"> (Details: UCUM code % = '%')</span></p></blockquote><blockquote><p><b>modelCharacteristic</b></p><p><b>code</b>: Meta-analysis <span style="background: LightGoldenRodYellow; margin: 4px; border: 1px solid khaki"> (<a href="http://hl7.org/fhir/R5/codesystem-statistic-model-code.html">Statistic Model Code</a>#metaAnalysis)</span></p></blockquote><blockquote><p><b>modelCharacteristic</b></p><p><b>code</b>: Random-effects <span style="background: LightGoldenRodYellow; margin: 4px; border: 1px solid khaki"> (<a href="http://hl7.org/fhir/R5/codesystem-statistic-model-code.html">Statistic Model Code</a>#effectsRandom)</span></p></blockquote></blockquote></div>
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  <name value="MeanDiffA1c2016metaAnalysis"/>
  <title
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  <status value="active"/>
  <date value="2022-05-28T12:01:55.472Z"/>
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    <name value="Brian S. Alper"/>
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    <display value="Figure 2C"/>
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               value="effect estimate for differences in mean HbA1c at study end point between Surgery and Medical/Lifestyle groups -1.14% (95% CI -1.57% to -0.71%) in meta-analysis of 15 trials with 1,067 participants"/>
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               url="http://hl7.org/fhir/uv/ebm/StructureDefinition/variable-definition-variable-role-code">
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    <description
                 value="Patients with type 2 diabetes *NOTE: note.text is used artificially to support the EBMonFHIR Implementation Guide and the following content would more properly be found in a note.text element:* The observed element can reference a Group Resource that represents an actual group of studies included and has a quantity.  The quantity would be the number of members (number of studies), and the characteristic can be code 'Member of' and valueReference EvidenceList with an EvidenceList that can reference the Evidence Resources representing the individual study results. This meta-analysis included 15 studies. The intended element (if desired) can reference a Group Resource that expresses the population of studies intended for evidence application through structured characteristics. The structured characteristics could be used to express the SR eligibility criteria for participants (i.e. included studies). The included trials included patients with T2D, including mainly individuals with BMI ≥35 kg/m2 (the most commonly used threshold for traditional bariatric surgery) as well as some patients with BMI &lt;35 kg/m2 (range 25–35 kg/m2)."/>
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      <reference value="Group/33395"/>
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    <description
                 value="Any of 4 bariatric surgery procedures (Roux-en-Y Gastric Bypass, Vertical Sleeve Gastrectomy, Laparoscopic Adjustable Gastric banding, Biliopancreatic Diversion) vs. Medical/lifestyle interventions *NOTE: note.text is used artificially to support the EBMonFHIR Implementation Guide and the following content would more properly be found in a note.text element:* As the control group (observed reference exposure) was defined differently in each trial, the intended reference exposure is described as the absence of the intended exposure (Bariatric Surgery)."/>
    <note>
      <text value="exposure"/>
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    <variableRole>
      <coding>
        <system value="http://terminology.hl7.org/CodeSystem/variable-role"/>
        <code value="exposure"/>
        <display value="exposure"/>
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      <text value="Use extension:variableRoleCode instead."/>
    </variableRole>
    <intended>🔗 
      <reference value="EvidenceVariable/172427"/>
      <type value="EvidenceVariable"/>
      <display
               value="GroupAssignment: Bariatric Surgery vs. no bariatric surgery"/>
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    <description
                 value="Mean difference in HbA1c between Surgery and Medical/Lifestyle groups at end of follow-up for HbA1c end point"/>
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      <coding>
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        <display value="measured variable"/>
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      <text value="Use extension:variableRoleCode instead."/>
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    <observed>🔗 
      <reference value="EvidenceVariable/46025"/>
      <type value="EvidenceVariable"/>
      <display
               value="OutcomeVariable: Mean difference in HbA1c between Surgery and Medical/Lifestyle groups at end of follow-up for HbA1c end point"/>
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  <statistic>
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                 value="mean difference in HbA1c -1.14% (95% CI -1.57% to -0.71%)"/>
    <note>
      <text
            value="random-effects model, heterogeneity tau-squared 0.63; chi-squared 200.88, df 14 (p &lt; 0.00001), I-squared 93%"/>
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      <unit value="%"/>
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      <description
                   value="15 studies with 1067 participants contributing to analysis"/>
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    <attributeEstimate>
      <description value="95% CI -1.57% to -0.71%"/>
      <type>
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          <code value="C53324"/>
          <display value="Confidence interval"/>
        </coding>
      </type>
      <level value="0.95"/>
      <range>
        <low>
          <value value="-1.57"/>
          <unit value="%"/>
          <system value="http://unitsofmeasure.org"/>
          <code value="%"/>
        </low>
        <high>
          <value value="-0.71"/>
          <unit value="%"/>
          <system value="http://unitsofmeasure.org"/>
          <code value="%"/>
        </high>
      </range>
    </attributeEstimate>
    <attributeEstimate>
      <description value="z = 5.20"/>
      <type>
        <coding>
          <system value="https://fevir.net/resources/CodeSystem/179423"/>
          <code value="defined-in-text"/>
          <display value="Defined in text"/>
        </coding>
        <text value="Z-score"/>
      </type>
      <quantity>
        <value value="5.2"/>
      </quantity>
    </attributeEstimate>
    <attributeEstimate>
      <description value="p &lt; 0.00001"/>
      <type>
        <coding>
          <system
                  value="http://terminology.hl7.org/CodeSystem/attribute-estimate-type"/>
          <code value="C44185"/>
          <display value="P-value"/>
        </coding>
      </type>
      <quantity>
        <value value="0.00001"/>
        <comparator value="&lt;"/>
      </quantity>
    </attributeEstimate>
    <attributeEstimate>
      <description value="Tau squared = 0.63"/>
      <type>
        <coding>
          <system
                  value="http://terminology.hl7.org/CodeSystem/attribute-estimate-type"/>
          <code value="0000421"/>
          <display value="Tau squared"/>
        </coding>
      </type>
      <quantity>
        <value value="0.63"/>
      </quantity>
    </attributeEstimate>
    <attributeEstimate>
      <description
                   value="Chi square for homogeneity 200.88, df 14 (p &lt; 0.00001)"/>
      <type>
        <coding>
          <system value="https://fevir.net/resources/CodeSystem/179423"/>
          <code value="defined-in-text"/>
          <display value="Defined in text"/>
        </coding>
        <text value="Chi square for homogeneity"/>
      </type>
      <quantity>
        <value value="200.88"/>
      </quantity>
      <attributeEstimate>
        <description value="degrees of freedom (df) = 14"/>
        <type>
          <coding>
            <system value="https://fevir.net/resources/CodeSystem/179423"/>
            <code value="defined-in-text"/>
            <display value="Defined in text"/>
          </coding>
          <text value="Degrees of Freedom"/>
        </type>
        <quantity>
          <value value="14"/>
        </quantity>
      </attributeEstimate>
      <attributeEstimate>
        <description value="p &lt; 0.00001"/>
        <type>
          <coding>
            <system
                    value="http://terminology.hl7.org/CodeSystem/attribute-estimate-type"/>
            <code value="C44185"/>
            <display value="P-value"/>
          </coding>
        </type>
        <quantity>
          <value value="0.00001"/>
          <comparator value="&lt;"/>
        </quantity>
      </attributeEstimate>
    </attributeEstimate>
    <attributeEstimate>
      <description value="I-squared = 93%"/>
      <type>
        <coding>
          <system
                  value="http://terminology.hl7.org/CodeSystem/attribute-estimate-type"/>
          <code value="0000420"/>
          <display value="I-squared"/>
        </coding>
      </type>
      <quantity>
        <value value="93"/>
        <unit value="%"/>
        <system value="http://unitsofmeasure.org"/>
        <code value="%"/>
      </quantity>
    </attributeEstimate>
    <modelCharacteristic>
      <code>
        <coding>
          <system value="http://hl7.org/fhir/statistic-model-code"/>
          <code value="metaAnalysis"/>
          <display value="Meta-analysis"/>
        </coding>
      </code>
    </modelCharacteristic>
    <modelCharacteristic>
      <code>
        <coding>
          <system value="http://hl7.org/fhir/statistic-model-code"/>
          <code value="effectsRandom"/>
          <display value="Random-effects"/>
        </coding>
      </code>
    </modelCharacteristic>
  </statistic>
</Evidence>