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 2.0.0-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 - JSON Representation

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{
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    "div" : "<div xmlns=\"http://www.w3.org/1999/xhtml\"><p class=\"res-header-id\"><b>Generated Narrative: Evidence 33244</b></p><a name=\"33244\"> </a><a name=\"hc33244\"> </a><a name=\"33244-en-US\"> </a><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\">version: 36; Last updated: 2023-12-08 16:30:32+0000</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>: <a href=\"https://fevir.net/resources/Evidence/33244\">https://fevir.net/resources/Evidence/33244</a></p><p><b>identifier</b>: FEvIR Object Identifier/33244</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>: Computable Publishing LLC</p><p><b>contact</b>: <a href=\"mailto:support@computablepublishing.com\">support@computablepublishing.com</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><a href=\"CodeSystem-179423.html#179423-evidence-communication\">Evidence Based Medicine on FHIR Implementation Guide Code System evidence-communication</a>: Evidence Communication</td><td><span title=\"Codes:{https://fevir.net/resources/CodeSystem/179423 ComparativeEvidence}\">ComparativeEvidence</span></td></tr><tr><td style=\"display: none\">*</td><td><a href=\"CodeSystem-179423.html#179423-evidence-communication\">Evidence Based Medicine on FHIR Implementation Guide Code System evidence-communication</a>: Evidence Communication</td><td><span title=\"Codes:{https://fevir.net/resources/CodeSystem/179423 EvidenceSynthesisEvidence}\">EvidenceSynthesisEvidence</span></td></tr></table><p><b>copyright</b>: </p><div><p>https://creativecommons.org/licenses/by-nc-sa/4.0/</p>\n</div><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>: </p><div><p>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>\n</div><h3>Documents</h3><table class=\"grid\"><tr><td style=\"display: none\">-</td><td><b>Url</b></td></tr><tr><td style=\"display: none\">*</td><td><a href=\"https://diabetesjournals.org/care/article/39/6/861/29305/Metabolic-Surgery-in-the-Treatment-Algorithm-for\">https://diabetesjournals.org/care/article/39/6/861/29305/Metabolic-Surgery-in-the-Treatment-Algorithm-for</a></td></tr></table></blockquote><blockquote><p><b>relatedArtifact</b></p><p><b>type</b>: Supported With</p><p><b>classifier</b>: <span title=\"Codes:\">Citation Resource for the original article</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\">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>: </p><div><p>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>\n</div></blockquote><p><b>description</b>: </p><div><p>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>\n</div><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>description</b>: </p><div><p>Patients with type 2 diabetes <em>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:</em> 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>\n</div><p><b>variableRole</b>: Population</p><p><b>observed</b>: <a href=\"Group-33395.html\">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\">MetaanalysisEligibilityCriteria: Mean difference in HbA1c effect of bariatric surgery in type 2 diabetes and elevated BMI in 2016 meta-analysis</a></p></blockquote><blockquote><p><b>variableDefinition</b></p><p><b>description</b>: </p><div><p>Any of 4 bariatric surgery procedures (Roux-en-Y Gastric Bypass, Vertical Sleeve Gastrectomy, Laparoscopic Adjustable Gastric banding, Biliopancreatic Diversion) vs. Medical/lifestyle interventions <em>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:</em> 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>\n</div><p><b>variableRole</b>: Exposure</p><p><b>comparatorCategory</b>: no bariatric surgery</p><p><b>intended</b>: <a href=\"EvidenceVariable-172427.html\">GroupAssignment: Bariatric Surgery vs. no bariatric surgery</a></p></blockquote><blockquote><p><b>variableDefinition</b></p><p><b>description</b>: </p><div><p>Mean difference in HbA1c between Surgery and Medical/Lifestyle groups at end of follow-up for HbA1c end point</p>\n</div><p><b>variableRole</b>: Outcome</p><p><b>observed</b>: <a href=\"EvidenceVariable-46025.html\">OutcomeVariable: Mean difference in HbA1c between Surgery and Medical/Lifestyle groups at end of follow-up for HbA1c end point</a></p></blockquote><p><b>synthesisType</b>: <span title=\"Codes:{http://terminology.hl7.org/CodeSystem/synthesis-type std-MA}\">summary data meta-analysis</span></p><p><b>studyDesign</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:01003}\">randomized assignment</span></p><blockquote><p><b>statistic</b></p><p><b>description</b>: </p><div><p>mean difference in HbA1c -1.14% (95% CI -1.57% to -0.71%)</p>\n</div><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>: <span title=\"Codes:{http://terminology.hl7.org/CodeSystem/statistic-type 0000457}\">A mean of values in which each value is the subtraction of one quantity from another.</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><div><p>15 studies with 1067 participants contributing to analysis</p>\n</div></td><td>15</td><td>0</td><td>1067</td></tr></table><blockquote><p><b>attributeEstimate</b></p><p><b>description</b>: </p><div><p>95% CI -1.57% to -0.71%</p>\n</div><p><b>type</b>: <span title=\"Codes:{http://terminology.hl7.org/CodeSystem/attribute-estimate-type C53324}\">Confidence interval</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>: </p><div><p>z = 5.20</p>\n</div><p><b>type</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/179423 defined-in-text}\">Z-score</span></p><p><b>quantity</b>: 5.2</p></blockquote><blockquote><p><b>attributeEstimate</b></p><p><b>description</b>: </p><div><p>p &lt; 0.00001</p>\n</div><p><b>type</b>: <span title=\"Codes:{http://terminology.hl7.org/CodeSystem/attribute-estimate-type C44185}\">P-value</span></p><p><b>quantity</b>: &lt;1e-05</p></blockquote><blockquote><p><b>attributeEstimate</b></p><p><b>description</b>: </p><div><p>Tau squared = 0.63</p>\n</div><p><b>type</b>: <span title=\"Codes:{http://terminology.hl7.org/CodeSystem/attribute-estimate-type 0000421}\">Tau squared</span></p><p><b>quantity</b>: 0.63</p></blockquote><blockquote><p><b>attributeEstimate</b></p><p><b>description</b>: </p><div><p>Chi square for homogeneity 200.88, df 14 (p &lt; 0.00001)</p>\n</div><p><b>type</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/179423 defined-in-text}\">Chi square for homogeneity</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><div><p>degrees of freedom (df) = 14</p>\n</div></td><td><span title=\"Codes:{https://fevir.net/resources/CodeSystem/179423 defined-in-text}\">Degrees of Freedom</span></td><td>14</td></tr><tr><td style=\"display: none\">*</td><td><div><p>p &lt; 0.00001</p>\n</div></td><td><span title=\"Codes:{http://terminology.hl7.org/CodeSystem/attribute-estimate-type C44185}\">P-value</span></td><td>&lt;1e-05</td></tr></table></blockquote><blockquote><p><b>attributeEstimate</b></p><p><b>description</b>: </p><div><p>I-squared = 93%</p>\n</div><p><b>type</b>: <span title=\"Codes:{http://terminology.hl7.org/CodeSystem/attribute-estimate-type 0000420}\">I-squared</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>: <span title=\"Codes:{http://hl7.org/fhir/statistic-model-code metaAnalysis}\">Meta-analysis</span></p></blockquote><blockquote><p><b>modelCharacteristic</b></p><p><b>code</b>: <span title=\"Codes:{http://hl7.org/fhir/statistic-model-code effectsRandom}\">Random-effects</span></p></blockquote></blockquote></div>"
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}