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

: Risk of Bias Assessment of Critically appraised summary of primary outcome of multi-platform RCT of anticoagulation for non-critically ill patients with COVID-19 - TTL Representation

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@prefix fhir: <http://hl7.org/fhir/> .
@prefix owl: <http://www.w3.org/2002/07/owl#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .

# - resource -------------------------------------------------------------------

 a fhir:ArtifactAssessment ;
  fhir:nodeRole fhir:treeRoot ;
  fhir:id [ fhir:v "179692"] ; # 
  fhir:meta [
fhir:versionId [ fhir:v "5" ] ;
fhir:lastUpdated [ fhir:v "2023-12-08T00:46:44.190Z"^^xsd:dateTime ] ;
    ( fhir:profile [
fhir:v "http://hl7.org/fhir/uv/ebm/StructureDefinition/risk-of-bias"^^xsd:anyURI ;
fhir:link <http://hl7.org/fhir/uv/ebm/StructureDefinition/risk-of-bias>     ] )
  ] ; # 
  fhir:text [
fhir:status [ fhir:v "extensions" ] ;
fhir:div "<div xmlns=\"http://www.w3.org/1999/xhtml\"><p class=\"res-header-id\"><b>Generated Narrative: ArtifactAssessment 179692</b></p><a name=\"179692\"> </a><a name=\"hc179692\"> </a><a name=\"179692-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: 5; Last updated: 2023-12-08 00:46:44+0000</p><p style=\"margin-bottom: 0px\">Profile: <a href=\"StructureDefinition-risk-of-bias.html\">RiskOfBias</a></p></div><p><b>Artifact URL</b>: <a href=\"https://fevir.net/resources/ArtifactAssessment/179692\">https://fevir.net/resources/ArtifactAssessment/179692</a></p><p><b>Artifact Description</b>: </p><div><p>The ArtifactAssessment Resource is used here to show a complex risk of bias assessment with multiple recursive components.</p>\n</div><p><b>identifier</b>: FEvIR Object Identifier/179692</p><p><b>title</b>: Risk of Bias Assessment of Critically appraised summary of primary outcome of multi-platform RCT of anticoagulation for non-critically ill patients with COVID-19</p><p><b>date</b>: 2021-12-29 22:35:49+0000</p><p><b>copyright</b>: </p><div><p>https://creativecommons.org/licenses/by-nc-sa/4.0/</p>\n</div><p><b>artifact</b>: <a href=\"Evidence-7637.html\">Critically appraised summary of primary outcome of multi-platform RCT of anticoagulation for non-critically ill patients with COVID-19</a></p><blockquote><p><b>content</b></p><p><b>informationType</b>: Rating</p><p><b>type</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00001}\">Bias</span></p><p><b>classifier</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00190}\">Critical risk of bias</span></p><p><b>author</b>: Brian S. Alper, Harold Lehmann, Ahmad Sofi-Mahmudi, Joanne Dehnbostel, Ilkka Kunnamo, Alfonso Iorio</p><p><b>freeToShare</b>: true</p><blockquote><p><b>component</b></p><p><b>informationType</b>: Rating</p><p><b>summary</b>: </p><div><p>Inclusion of suspected COVID-19 in 1 of 3 trials may introduce selection bias, but the impact appears limited.</p>\n</div><p><b>type</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00003}\">Participant Selection Bias</span></p><p><b>classifier</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00209}\">Factor likely does not have potential to impact results</span>, <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00186}\">Low risk of bias</span></p><h3>Components</h3><table class=\"grid\"><tr><td style=\"display: none\">-</td><td><b>InformationType</b></td><td><b>Summary</b></td></tr><tr><td style=\"display: none\">*</td><td>Comment</td><td><div><p>Participant Selection Bias Definition: A selection bias resulting from methods used to select participating subjects, factors that influence initial study participation, or differences between the study participants and the population of interest.</p>\n</div></td></tr></table></blockquote><blockquote><p><b>component</b></p><p><b>informationType</b>: Rating</p><p><b>summary</b>: </p><div><p>The study design used response-adaptive randomization in which group assignment ratios could be modified during the trial on the basis of response-adaptive interim analyses to favor the assignment of patients to the treatment group showing greater benefit. The confounding by time (imbalanced randomization with time period) is not adequately reported to determine the potential influence on results or adequacy of adjusted analyses.</p>\n</div><p><b>type</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00016}\">Confounding Covariate Bias</span></p><p><b>classifier</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00189}\">Serious risk of bias</span></p><blockquote><p><b>component</b></p><p><b>informationType</b>: Rating</p><p><b>summary</b>: </p><div><p>Response-adaptive randomization led to imbalanced randomization.</p>\n</div><p><b>type</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00032}\">Allocation Bias</span></p><h3>Components</h3><table class=\"grid\"><tr><td style=\"display: none\">-</td><td><b>InformationType</b></td><td><b>Summary</b></td></tr><tr><td style=\"display: none\">*</td><td>Comment</td><td><div><p>Adaptive randomization is not a concern by itself, only if it results in a confounding difference.</p>\n</div></td></tr><tr><td style=\"display: none\">*</td><td>Comment</td><td><div><p>Definition of Allocation Bias = A confounding covariate bias resulting from methods for assignment of the independent variable by the investigator to evaluate a response or outcome.</p>\n</div></td></tr><tr><td style=\"display: none\">*</td><td>Comment</td><td><div><p>ATTACC implemented response-adaptive randomization on December 15, 2020, which led to imbalanced randomization.</p>\n</div></td></tr></table></blockquote><blockquote><p><b>component</b></p><p><b>informationType</b>: Rating</p><p><b>summary</b>: </p><div><p>There is an unequal distribution of calendar time between the groups being compared.</p>\n</div><p><b>type</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00034}\">Confounding difference</span></p><p><b>classifier</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00194}\">Factor present</span>, <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00207}\">Factor has potential to impact results</span>, <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00201}\">Risk of bias favoring experimental</span>, <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00189}\">Serious risk of bias</span></p><h3>Components</h3><table class=\"grid\"><tr><td style=\"display: none\">-</td><td><b>InformationType</b></td><td><b>Summary</b></td></tr><tr><td style=\"display: none\">*</td><td>Comment</td><td><div><p>Definition of Confounding difference = A confounding covariate bias in which the unequal distribution of a potentially distorting variable is recognized.</p>\n</div></td></tr><tr><td style=\"display: none\">*</td><td>Comment</td><td><div><p>Incomplete reporting limits the determination of the potential degree of influence of calendar time.</p>\n</div></td></tr><tr><td style=\"display: none\">*</td><td>Comment</td><td><div><p>There is evidence of potential for calendar time to influence the results: In an observational study of 18,508 adults with laboratory-confirmed, COVID-19 associated hospitalization 'The percentage of hospitalized patients admitted to the ICU decreased from 37.8% in March to 20.5% in December' (Ann Intern Med 2021 Aug 10 https://www.acpjournals.org/doi/10.7326/M21-1991).</p>\n</div></td></tr></table></blockquote><blockquote><p><b>component</b></p><p><b>informationType</b>: Comment</p><p><b>summary</b>: </p><div><p>Definition of Confounding Covariate Bias = A situation in which the effect or association between an exposure and outcome is distorted by another variable. For confounding covariate bias to occur the distorting variable must be (1) associated with the exposure and the outcome, (2) not in the causal pathway between exposure and outcome, and (3) unequally distributed between the groups being compared.</p>\n</div></blockquote><blockquote><p><b>component</b></p><p><b>informationType</b>: Comment</p><p><b>summary</b>: </p><div><p>ATTACC implemented response-adaptive randomization on December 15, 2020, which led to imbalanced randomization. No data reported to determine if intervention-specific outcome rates were similar or different before and after December 15, 2020 in the ATTACC cohort.</p>\n</div></blockquote><blockquote><p><b>component</b></p><p><b>informationType</b>: Comment</p><p><b>summary</b>: </p><div><p>Insufficient details reported to judge whether there is an imbalance in outcomes related to the adaptive randomization which in turn could be used to judge the validity of adjustment methods in the statistical model for this concern and the appropriateness of any sensitivity analyses.</p>\n</div></blockquote></blockquote><blockquote><p><b>component</b></p><p><b>informationType</b>: Rating</p><p><b>summary</b>: </p><div><p>Awareness of treatment assignment may reduce clinical decision to initiate some types of &quot;organ support&quot; in patients with higher risk of major bleeding.</p>\n</div><p><b>type</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00017}\">Performance Bias</span></p><p><b>classifier</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00207}\">Factor has potential to impact results</span>, <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00201}\">Risk of bias favoring experimental</span>, <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00190}\">Critical risk of bias</span></p><blockquote><p><b>component</b></p><p><b>informationType</b>: Rating</p><p><b>summary</b>: </p><div><p>Lack of blinding may explain reported differences in the primary outcome.</p>\n</div><p><b>type</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00036}\">Inadequate blinding of intervention deliverers</span></p><p><b>classifier</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00190}\">Critical risk of bias</span></p><h3>Components</h3><table class=\"grid\"><tr><td style=\"display: none\">-</td><td><b>InformationType</b></td><td><b>Summary</b></td></tr><tr><td style=\"display: none\">*</td><td>Comment</td><td><div><p>The absolute difference in survival without intubation was 1%, so 3% of the 4% absolute difference in the primary outcome can be considered &quot;organ support without intubation&quot;.</p>\n</div></td></tr><tr><td style=\"display: none\">*</td><td>Comment</td><td><div><p>The specific &quot;organ support without intubation&quot; was not reported. The methods for one of the included trials stated &quot;Organ Support is defined as receipt of invasive or non-invasive mechanical ventilation, high flow nasal oxygen, vasopressor therapy, or ECMO support&quot;</p>\n</div></td></tr><tr><td style=\"display: none\">*</td><td>Comment</td><td><div><p>Awareness of treatment assignment may reduce clinical decision to initiate &quot;organ support without intubation&quot; in patients with higher risk of major bleeding.</p>\n</div></td></tr></table></blockquote><blockquote><p><b>component</b></p><p><b>informationType</b>: Rating</p><p><b>summary</b>: </p><div><p>Crossover to other intervention in 20%</p>\n</div><p><b>type</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00037}\">Deviation from study intervention protocol</span></p><p><b>classifier</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00192}\">Unclear risk of bias</span></p><h3>Components</h3><table class=\"grid\"><tr><td style=\"display: none\">-</td><td><b>InformationType</b></td><td><b>Summary</b></td></tr><tr><td style=\"display: none\">*</td><td>Comment</td><td><div><p>Therapeutic dose anticoagulation (in the first 24-48 hours following randomization) was reported in 79.6% of the therapeutic arm and 0.9% of the usual care arm. (Table S3)</p>\n</div></td></tr><tr><td style=\"display: none\">*</td><td>Comment</td><td><div><p>Definition of Deviation from study intervention protocol = A performance bias in which the intervention received differs from the intervention specified in the study protocol.</p>\n</div></td></tr></table></blockquote><blockquote><p><b>component</b></p><p><b>informationType</b>: Rating</p><p><b>summary</b>: </p><div><p>We discussed whether they may be a bias related to limited adherence to anticoagulation. Because this was an inpatient population, we did not expect adherence problems that are more common with outpatient thromboprophylaxis.</p>\n</div><p><b>type</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00039}\">Nonadherence of implementation</span></p><p><b>classifier</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00196}\">Factor likely absent</span>, <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00186}\">Low risk of bias</span></p><h3>Components</h3><table class=\"grid\"><tr><td style=\"display: none\">-</td><td><b>InformationType</b></td><td><b>Summary</b></td></tr><tr><td style=\"display: none\">*</td><td>Comment</td><td><div><p>Initial adherence to the protocol-assigned anticoagulation dose after randomization was 88.3% in the therapeutic-dose anticoagulation group and 98.3% in the thromboprophylaxis group (Table S3).</p>\n</div></td></tr></table></blockquote><blockquote><p><b>component</b></p><p><b>informationType</b>: Comment</p><p><b>summary</b>: </p><div><p>Definition of Performance Bias = A bias resulting from differences between the received exposure and the intended exposure.</p>\n</div></blockquote></blockquote><blockquote><p><b>component</b></p><p><b>informationType</b>: Rating</p><p><b>summary</b>: </p><div><p>The influence of awareness of treatment assignment by the treating clinicians on the initiation of organ support (which is the primary outcome) was already addressed as Performance Bias so is not repeated here as a bias in detecting the outcome.</p>\n</div><p><b>type</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00020}\">Detection Bias</span></p><p><b>classifier</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00186}\">Low risk of bias</span></p></blockquote><blockquote><p><b>component</b></p><p><b>informationType</b>: Rating</p><p><b>summary</b>: </p><div><p>Only 19 of 1190 (1.6%) therapeutic group and 6 of 1054 (0.6%) prophylactic group were excluded after randomization.</p>\n</div><p><b>type</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00019}\">Attrition Bias</span></p><p><b>classifier</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00186}\">Low risk of bias</span></p></blockquote><blockquote><p><b>component</b></p><p><b>informationType</b>: Rating</p><p><b>summary</b>: </p><div><p>It is unknown if the results are sensitive to the analytic method, and the stopping criteria were based on statistical significance and not magnitude of effect.</p>\n</div><p><b>type</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00021}\">Analysis Bias</span></p><p><b>classifier</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00190}\">Critical risk of bias</span></p><blockquote><p><b>component</b></p><p><b>informationType</b>: Rating</p><p><b>summary</b>: </p><div><p>A frequentist analysis is not reported so we cannot determine if the results are sensitive to the analytic method</p>\n</div><p><b>type</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00022}\">Bias related to selection of the analysis</span></p><p><b>classifier</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00195}\">Factor likely present</span>, <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00207}\">Factor has potential to impact results</span>, <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00201}\">Risk of bias favoring experimental</span>, <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00192}\">Unclear risk of bias</span></p><blockquote><p><b>component</b></p><p><b>informationType</b>: Rating</p><p><b>summary</b>: </p><div><p>The stopping criteria were based on statistical significance and not magnitude of effect.</p>\n</div><p><b>type</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00212}\">Early termination bias affecting enrollment</span></p><p><b>classifier</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00194}\">Factor present</span>, <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00207}\">Factor has potential to impact results</span>, <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00201}\">Risk of bias favoring experimental</span>, <span title=\"Codes:{https://fevir.net/resources/CodeSystem/181513 SEVCO:00190}\">Critical risk of bias</span></p><h3>Components</h3><table class=\"grid\"><tr><td style=\"display: none\">-</td><td><b>InformationType</b></td><td><b>Summary</b></td></tr><tr><td style=\"display: none\">*</td><td>Comment</td><td><div><p>There was no “minimally important difference”. So a 99% probability of having an odds ratio &gt; 1 (even if the magnitude of effect is infinitesimal) was used to decide it was time to stop the trial.</p>\n</div></td></tr></table></blockquote><blockquote><p><b>component</b></p><p><b>informationType</b>: Comment</p><p><b>summary</b>: </p><div><p>Definition of Bias related to selection of the analysis = An analysis bias due to inappropriate choice of analysis methods before the analysis is applied.</p>\n</div></blockquote><blockquote><p><b>component</b></p><p><b>informationType</b>: Comment</p><p><b>summary</b>: </p><div><p>There was no pre-specified frequentist analysis. There was no posthoc frequentist analysis reported.</p>\n</div></blockquote><blockquote><p><b>component</b></p><p><b>informationType</b>: Comment</p><p><b>summary</b>: </p><div><p>It is uncertain what a frequentist analysis would show and uncertain whether the choice of Bayesian analysis or frequentist analysis has a substantial influence on the results.</p>\n</div></blockquote></blockquote></blockquote></blockquote><blockquote><p><b>content</b></p><p><b>informationType</b>: Classifier</p><p><b>type</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/179423 defined-in-text}\">Profile for use with Risk of Bias Assessment Tool</span></p><p><b>classifier</b>: <span title=\"Codes:{https://fevir.net/resources/CodeSystem/179423 defined-in-text}\">Randomized trial</span></p></blockquote></div>"
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fhir:value [ fhir:v "The ArtifactAssessment Resource is used here to show a complex risk of bias assessment with multiple recursive components." ]
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fhir:display [ fhir:v "Computable Publishing LLC" ]     ]
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  fhir:title [ fhir:v "Risk of Bias Assessment of Critically appraised summary of primary outcome of multi-platform RCT of anticoagulation for non-critically ill patients with COVID-19"] ; # 
  fhir:date [ fhir:v "2021-12-29T22:35:49.782Z"^^xsd:dateTime] ; # 
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a fhir:Reference ;
fhir:reference [ fhir:v "Evidence/7637" ] ;
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fhir:display [ fhir:v "Critically appraised summary of primary outcome of multi-platform RCT of anticoagulation for non-critically ill patients with COVID-19" ]
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fhir:display [ fhir:v "Bias" ]       ] )     ] ;
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fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00190" ] ;
fhir:display [ fhir:v "Critical risk of bias" ]       ] )     ] ) ;
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fhir:display [ fhir:v "Brian S. Alper, Harold Lehmann, Ahmad Sofi-Mahmudi, Joanne Dehnbostel, Ilkka Kunnamo, Alfonso Iorio" ]     ] ;
fhir:freeToShare [ fhir:v "true"^^xsd:boolean ] ;
    ( fhir:component [
fhir:informationType [ fhir:v "rating" ] ;
fhir:summary [ fhir:v "Inclusion of suspected COVID-19 in 1 of 3 trials may introduce selection bias, but the impact appears limited." ] ;
fhir:type [
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fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00003" ] ;
fhir:display [ fhir:v "Participant Selection Bias" ]         ] )       ] ;
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fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00209" ] ;
fhir:display [ fhir:v "Factor likely does not have potential to impact results" ]         ] )       ] [
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fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00186" ] ;
fhir:display [ fhir:v "Low risk of bias" ]         ] )       ] ) ;
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fhir:informationType [ fhir:v "comment" ] ;
fhir:summary [ fhir:v "Participant Selection Bias Definition: A selection bias resulting from methods used to select participating subjects, factors that influence initial study participation, or differences between the study participants and the population of interest." ]       ] )     ] [
fhir:informationType [ fhir:v "rating" ] ;
fhir:summary [ fhir:v "The study design used response-adaptive randomization in which group assignment ratios could be modified during the trial on the basis of response-adaptive interim analyses to favor the assignment of patients to the treatment group showing greater benefit. The confounding by time (imbalanced randomization with time period) is not adequately reported to determine the potential influence on results or adequacy of adjusted analyses." ] ;
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fhir:display [ fhir:v "Confounding Covariate Bias" ]         ] )       ] ;
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fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00189" ] ;
fhir:display [ fhir:v "Serious risk of bias" ]         ] )       ] ) ;
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fhir:informationType [ fhir:v "rating" ] ;
fhir:summary [ fhir:v "Response-adaptive randomization led to imbalanced randomization." ] ;
fhir:type [
          ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00032" ] ;
fhir:display [ fhir:v "Allocation Bias" ]           ] )         ] ;
        ( fhir:component [
fhir:informationType [ fhir:v "comment" ] ;
fhir:summary [ fhir:v "Adaptive randomization is not a concern by itself, only if it results in a confounding difference." ]         ] [
fhir:informationType [ fhir:v "comment" ] ;
fhir:summary [ fhir:v "Definition of Allocation Bias = A confounding covariate bias resulting from methods for assignment of the independent variable by the investigator to evaluate a response or outcome." ]         ] [
fhir:informationType [ fhir:v "comment" ] ;
fhir:summary [ fhir:v "ATTACC implemented response-adaptive randomization on December 15, 2020, which led to imbalanced randomization." ]         ] )       ] [
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        ( fhir:classifier [
          ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00194" ] ;
fhir:display [ fhir:v "Factor present" ]           ] )         ] [
          ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00207" ] ;
fhir:display [ fhir:v "Factor has potential to impact results" ]           ] )         ] [
          ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00201" ] ;
fhir:display [ fhir:v "Risk of bias favoring experimental" ]           ] )         ] [
          ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00189" ] ;
fhir:display [ fhir:v "Serious risk of bias" ]           ] )         ] ) ;
        ( fhir:component [
fhir:informationType [ fhir:v "comment" ] ;
fhir:summary [ fhir:v "Definition of Confounding difference = A confounding covariate bias in which the unequal distribution of a potentially distorting variable is recognized." ]         ] [
fhir:informationType [ fhir:v "comment" ] ;
fhir:summary [ fhir:v "Incomplete reporting limits the determination of the potential degree of influence of calendar time." ]         ] [
fhir:informationType [ fhir:v "comment" ] ;
fhir:summary [ fhir:v "There is evidence of potential for calendar time to influence the results: In an observational study of 18,508 adults with laboratory-confirmed, COVID-19 associated hospitalization 'The percentage of hospitalized patients admitted to the ICU decreased from 37.8% in March to 20.5% in December' (Ann Intern Med 2021 Aug 10 https://www.acpjournals.org/doi/10.7326/M21-1991)." ]         ] )       ] [
fhir:informationType [ fhir:v "comment" ] ;
fhir:summary [ fhir:v "Definition of Confounding Covariate Bias = A situation in which the effect or association between an exposure and outcome is distorted by another variable. For confounding covariate bias to occur the distorting variable must be (1) associated with the exposure and the outcome, (2) not in the causal pathway between exposure and outcome, and (3) unequally distributed between the groups being compared." ]       ] [
fhir:informationType [ fhir:v "comment" ] ;
fhir:summary [ fhir:v "ATTACC implemented response-adaptive randomization on December 15, 2020, which led to imbalanced randomization. No data reported to determine if intervention-specific outcome rates were similar or different before and after December 15, 2020 in the ATTACC cohort." ]       ] [
fhir:informationType [ fhir:v "comment" ] ;
fhir:summary [ fhir:v "Insufficient details reported to judge whether there is an imbalance in outcomes related to the adaptive randomization which in turn could be used to judge the validity of adjustment methods in the statistical model for this concern and the appropriateness of any sensitivity analyses." ]       ] )     ] [
fhir:informationType [ fhir:v "rating" ] ;
fhir:summary [ fhir:v "Awareness of treatment assignment may reduce clinical decision to initiate some types of \"organ support\" in patients with higher risk of major bleeding." ] ;
fhir:type [
        ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00017" ] ;
fhir:display [ fhir:v "Performance Bias" ]         ] )       ] ;
      ( fhir:classifier [
        ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00207" ] ;
fhir:display [ fhir:v "Factor has potential to impact results" ]         ] )       ] [
        ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00201" ] ;
fhir:display [ fhir:v "Risk of bias favoring experimental" ]         ] )       ] [
        ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00190" ] ;
fhir:display [ fhir:v "Critical risk of bias" ]         ] )       ] ) ;
      ( fhir:component [
fhir:informationType [ fhir:v "rating" ] ;
fhir:summary [ fhir:v "Lack of blinding may explain reported differences in the primary outcome." ] ;
fhir:type [
          ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00036" ] ;
fhir:display [ fhir:v "Inadequate blinding of intervention deliverers" ]           ] )         ] ;
        ( fhir:classifier [
          ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00190" ] ;
fhir:display [ fhir:v "Critical risk of bias" ]           ] )         ] ) ;
        ( fhir:component [
fhir:informationType [ fhir:v "comment" ] ;
fhir:summary [ fhir:v "The absolute difference in survival without intubation was 1%, so 3% of the 4% absolute difference in the primary outcome can be considered \"organ support without intubation\"." ]         ] [
fhir:informationType [ fhir:v "comment" ] ;
fhir:summary [ fhir:v "The specific \"organ support without intubation\" was not reported. The methods for one of the included trials stated \"Organ Support is defined as receipt of invasive or non-invasive mechanical ventilation, high flow nasal oxygen, vasopressor therapy, or ECMO support\"" ]         ] [
fhir:informationType [ fhir:v "comment" ] ;
fhir:summary [ fhir:v "Awareness of treatment assignment may reduce clinical decision to initiate \"organ support without intubation\" in patients with higher risk of major bleeding." ]         ] )       ] [
fhir:informationType [ fhir:v "rating" ] ;
fhir:summary [ fhir:v "Crossover to other intervention in 20%" ] ;
fhir:type [
          ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00037" ] ;
fhir:display [ fhir:v "Deviation from study intervention protocol" ]           ] )         ] ;
        ( fhir:classifier [
          ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00192" ] ;
fhir:display [ fhir:v "Unclear risk of bias" ]           ] )         ] ) ;
        ( fhir:component [
fhir:informationType [ fhir:v "comment" ] ;
fhir:summary [ fhir:v "Therapeutic dose anticoagulation (in the first 24-48 hours following randomization) was reported in 79.6% of the therapeutic arm and 0.9% of the usual care arm. (Table S3)" ]         ] [
fhir:informationType [ fhir:v "comment" ] ;
fhir:summary [ fhir:v "Definition of Deviation from study intervention protocol = A performance bias in which the intervention received differs from the intervention specified in the study protocol." ]         ] )       ] [
fhir:informationType [ fhir:v "rating" ] ;
fhir:summary [ fhir:v "We discussed whether they may be a bias related to limited adherence to anticoagulation. Because this was an inpatient population, we did not expect adherence problems that are more common with outpatient thromboprophylaxis." ] ;
fhir:type [
          ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00039" ] ;
fhir:display [ fhir:v "Nonadherence of implementation" ]           ] )         ] ;
        ( fhir:classifier [
          ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00196" ] ;
fhir:display [ fhir:v "Factor likely absent" ]           ] )         ] [
          ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00186" ] ;
fhir:display [ fhir:v "Low risk of bias" ]           ] )         ] ) ;
        ( fhir:component [
fhir:informationType [ fhir:v "comment" ] ;
fhir:summary [ fhir:v "Initial adherence to the protocol-assigned anticoagulation dose after randomization was 88.3% in the therapeutic-dose anticoagulation group and 98.3% in the thromboprophylaxis group (Table S3)." ]         ] )       ] [
fhir:informationType [ fhir:v "comment" ] ;
fhir:summary [ fhir:v "Definition of Performance Bias = A bias resulting from differences between the received exposure and the intended exposure." ]       ] )     ] [
fhir:informationType [ fhir:v "rating" ] ;
fhir:summary [ fhir:v "The influence of awareness of treatment assignment by the treating clinicians on the initiation of organ support (which is the primary outcome) was already addressed as Performance Bias so is not repeated here as a bias in detecting the outcome." ] ;
fhir:type [
        ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00020" ] ;
fhir:display [ fhir:v "Detection Bias" ]         ] )       ] ;
      ( fhir:classifier [
        ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00186" ] ;
fhir:display [ fhir:v "Low risk of bias" ]         ] )       ] )     ] [
fhir:informationType [ fhir:v "rating" ] ;
fhir:summary [ fhir:v "Only 19 of 1190 (1.6%) therapeutic group and 6 of 1054 (0.6%) prophylactic group were excluded after randomization." ] ;
fhir:type [
        ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00019" ] ;
fhir:display [ fhir:v "Attrition Bias" ]         ] )       ] ;
      ( fhir:classifier [
        ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00186" ] ;
fhir:display [ fhir:v "Low risk of bias" ]         ] )       ] )     ] [
fhir:informationType [ fhir:v "rating" ] ;
fhir:summary [ fhir:v "It is unknown if the results are sensitive to the analytic method, and the stopping criteria were based on statistical significance and not magnitude of effect." ] ;
fhir:type [
        ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00021" ] ;
fhir:display [ fhir:v "Analysis Bias" ]         ] )       ] ;
      ( fhir:classifier [
        ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00190" ] ;
fhir:display [ fhir:v "Critical risk of bias" ]         ] )       ] ) ;
      ( fhir:component [
fhir:informationType [ fhir:v "rating" ] ;
fhir:summary [ fhir:v "A frequentist analysis is not reported so we cannot determine if the results are sensitive to the analytic method" ] ;
fhir:type [
          ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00022" ] ;
fhir:display [ fhir:v "Bias related to selection of the analysis" ]           ] )         ] ;
        ( fhir:classifier [
          ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00195" ] ;
fhir:display [ fhir:v "Factor likely present" ]           ] )         ] [
          ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00207" ] ;
fhir:display [ fhir:v "Factor has potential to impact results" ]           ] )         ] [
          ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00201" ] ;
fhir:display [ fhir:v "Risk of bias favoring experimental" ]           ] )         ] [
          ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00192" ] ;
fhir:display [ fhir:v "Unclear risk of bias" ]           ] )         ] ) ;
        ( fhir:component [
fhir:informationType [ fhir:v "rating" ] ;
fhir:summary [ fhir:v "The stopping criteria were based on statistical significance and not magnitude of effect." ] ;
fhir:type [
            ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00212" ] ;
fhir:display [ fhir:v "Early termination bias affecting enrollment" ]             ] )           ] ;
          ( fhir:classifier [
            ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00194" ] ;
fhir:display [ fhir:v "Factor present" ]             ] )           ] [
            ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00207" ] ;
fhir:display [ fhir:v "Factor has potential to impact results" ]             ] )           ] [
            ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00201" ] ;
fhir:display [ fhir:v "Risk of bias favoring experimental" ]             ] )           ] [
            ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/181513"^^xsd:anyURI ] ;
fhir:code [ fhir:v "SEVCO:00190" ] ;
fhir:display [ fhir:v "Critical risk of bias" ]             ] )           ] ) ;
          ( fhir:component [
fhir:informationType [ fhir:v "comment" ] ;
fhir:summary [ fhir:v "There was no “minimally important difference”. So a 99% probability of having an odds ratio > 1 (even if the magnitude of effect is infinitesimal) was used to decide it was time to stop the trial." ]           ] )         ] [
fhir:informationType [ fhir:v "comment" ] ;
fhir:summary [ fhir:v "Definition of Bias related to selection of the analysis = An analysis bias due to inappropriate choice of analysis methods before the analysis is applied." ]         ] [
fhir:informationType [ fhir:v "comment" ] ;
fhir:summary [ fhir:v "There was no pre-specified frequentist analysis. There was no posthoc frequentist analysis reported." ]         ] [
fhir:informationType [ fhir:v "comment" ] ;
fhir:summary [ fhir:v "It is uncertain what a frequentist analysis would show and uncertain whether the choice of Bayesian analysis or frequentist analysis has a substantial influence on the results." ]         ] )       ] )     ] )
  ] [
fhir:informationType [ fhir:v "classifier" ] ;
fhir:type [
      ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/179423"^^xsd:anyURI ] ;
fhir:code [ fhir:v "defined-in-text" ] ;
fhir:display [ fhir:v "Defined in text" ]       ] ) ;
fhir:text [ fhir:v "Profile for use with Risk of Bias Assessment Tool" ]     ] ;
    ( fhir:classifier [
      ( fhir:coding [
fhir:system [ fhir:v "https://fevir.net/resources/CodeSystem/179423"^^xsd:anyURI ] ;
fhir:code [ fhir:v "defined-in-text" ] ;
fhir:display [ fhir:v "Defined in text" ]       ] ) ;
fhir:text [ fhir:v "Randomized trial" ]     ] )
  ] ) . #