Observational studies using propensity score analysis underestimated the effect sizes in critical care medicine
Abstract Background and Objective Propensity score (PS) analysis has been increasingly used in critical care medicine; however, its validation has not been systematically investigated. The present study aimed to compare effect sizes in PS-based observational studies vs. randomized controlled trials...
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| Veröffentlicht in: | Journal of clinical epidemiology 2014-08, Vol.67 (8), p.932-939 |
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| description | Abstract Background and Objective Propensity score (PS) analysis has been increasingly used in critical care medicine; however, its validation has not been systematically investigated. The present study aimed to compare effect sizes in PS-based observational studies vs. randomized controlled trials (RCTs) (or meta-analysis of RCTs). Methods Critical care observational studies using PS were systematically searched in PubMed from inception to April 2013. Identified PS-based studies were matched to one or more RCTs in terms of population, intervention, comparison, and outcome. The effect sizes of experimental treatments were compared for PS-based studies vs. RCTs (or meta-analysis of RCTs) with sign test. Furthermore, ratio of odds ratio (ROR) was calculated from the interaction term of treatment × study type in a logistic regression model. A ROR < 1 indicates greater benefit for experimental treatment in RCTs compared with PS-based studies. RORs of each comparison were pooled by using meta-analytic approach with random-effects model. Results A total of 20 PS-based studies were identified and matched to RCTs. Twelve of the 20 comparisons showed greater beneficial effect for experimental treatment in RCTs than that in PS-based studies (sign test P = 0.503). The difference was statistically significant in four comparisons. ROR can be calculated from 13 comparisons, of which four showed significantly greater beneficial effect for experimental treatment in RCTs. The pooled ROR was 0.71 (95% CI: 0.63, 0.79; P = 0.002), suggesting that RCTs (or meta-analysis of RCTs) were more likely to report beneficial effect for the experimental treatment than PS-based studies. The result remained unchanged in sensitivity analysis and meta-regression. Conclusion In critical care literature, PS-based observational study is likely to report less beneficial effect of experimental treatment compared with RCTs (or meta-analysis of RCTs). |
| doi_str_mv | 10.1016/j.jclinepi.2014.02.018 |
| format | Article |
| fullrecord | <record><control><sourceid>proquest_cross</sourceid><recordid>TN_cdi_proquest_miscellaneous_1547853165</recordid><sourceformat>XML</sourceformat><sourcesystem>PC</sourcesystem><els_id>S0895435614000821</els_id><sourcerecordid>1547853165</sourcerecordid><originalsourceid>FETCH-LOGICAL-c580t-4a87e0e68f03549da02e4abb2153cc0e6636da460f82e75bcdf2b7a16bd95b293</originalsourceid><addsrcrecordid>eNqNkkFv1DAQhSMEotvCX6giISQuu4wd23EuiKqigFSpB-BsOc4EHLLJ4kkqLb-eSXdLpV7g5IO_9zTz3mTZuYCNAGHedpsu9HHAXdxIEGoDcgPCPslWwpZ2rSspnmYrsJVeq0Kbk-yUqAMQJZT6eXYiVVkqZapVNt7UhOnWT3EcfJ_TNDcRKZ8pDt_zXRp3OFCc9jmFMWHumdlT5P-hwYQ0xa2fsMmnH5hj22KYcoq_WR-HPKQ4xcCewbNyi00MPO-L7Fnre8KXx_cs-3b14evlp_X1zcfPlxfX66AtTGvlbYmAxrZQaFU1HiQqX9dS6CIE_jCFabwy0FqJpa5D08q69MLUTaVrWRVn2ZuDL-_wa-ZJ3TZSwL73A44zOaFVaXUhjP4PtKg4K1MAo68eod04Jw7ljjLCgCgsU-ZAhTQSJWzdLnFQae8EuKU917n79tzSngPpuD0Wnh_t55oD-yu7r4uB10fAE0fbJj-ESA-c5Vzs3fbvDxxyxLcRk6MQcQhcQuKSXDPGf8_y7pHFQi2F_sQ90sPejljgviy3tpyaUABgpSj-AHar0c0</addsrcrecordid><sourcetype>Aggregation Database</sourcetype><iscdi>true</iscdi><recordtype>article</recordtype><pqid>1536160138</pqid></control><display><type>article</type><title>Observational studies using propensity score analysis underestimated the effect sizes in critical care medicine</title><source>MEDLINE</source><source>Elsevier ScienceDirect Journals</source><creator>Zhang, Zhongheng ; Ni, Hongying ; Xu, Xiao</creator><creatorcontrib>Zhang, Zhongheng ; Ni, Hongying ; Xu, Xiao</creatorcontrib><description>Abstract Background and Objective Propensity score (PS) analysis has been increasingly used in critical care medicine; however, its validation has not been systematically investigated. The present study aimed to compare effect sizes in PS-based observational studies vs. randomized controlled trials (RCTs) (or meta-analysis of RCTs). Methods Critical care observational studies using PS were systematically searched in PubMed from inception to April 2013. Identified PS-based studies were matched to one or more RCTs in terms of population, intervention, comparison, and outcome. The effect sizes of experimental treatments were compared for PS-based studies vs. RCTs (or meta-analysis of RCTs) with sign test. Furthermore, ratio of odds ratio (ROR) was calculated from the interaction term of treatment × study type in a logistic regression model. A ROR < 1 indicates greater benefit for experimental treatment in RCTs compared with PS-based studies. RORs of each comparison were pooled by using meta-analytic approach with random-effects model. Results A total of 20 PS-based studies were identified and matched to RCTs. Twelve of the 20 comparisons showed greater beneficial effect for experimental treatment in RCTs than that in PS-based studies (sign test P = 0.503). The difference was statistically significant in four comparisons. ROR can be calculated from 13 comparisons, of which four showed significantly greater beneficial effect for experimental treatment in RCTs. The pooled ROR was 0.71 (95% CI: 0.63, 0.79; P = 0.002), suggesting that RCTs (or meta-analysis of RCTs) were more likely to report beneficial effect for the experimental treatment than PS-based studies. The result remained unchanged in sensitivity analysis and meta-regression. Conclusion In critical care literature, PS-based observational study is likely to report less beneficial effect of experimental treatment compared with RCTs (or meta-analysis of RCTs).</description><identifier>ISSN: 0895-4356</identifier><identifier>EISSN: 1878-5921</identifier><identifier>DOI: 10.1016/j.jclinepi.2014.02.018</identifier><identifier>PMID: 24774469</identifier><language>eng</language><publisher>New York, NY: Elsevier Inc</publisher><subject>Analysis. Health state ; Biological and medical sciences ; Clinical trials ; Confidence intervals ; Critical care ; Critical Care - methods ; Drug therapy ; Effect size ; Epidemiology ; General aspects ; Humans ; Intensive care ; Internal Medicine ; Intervention ; Logistic Models ; Medical sciences ; Medicine ; Meta-analysis ; Meta-Analysis as Topic ; Mortality ; Observational studies ; Observational Studies as Topic - methods ; Observational Studies as Topic - standards ; Observational study ; Odds Ratio ; Propensity Score ; Public health. Hygiene ; Public health. Hygiene-occupational medicine ; Randomized controlled trial ; Randomized Controlled Trials as Topic - methods ; Randomized Controlled Trials as Topic - standards ; Ratio of odds ratio ; Reproducibility of Results ; Research Design ; Sensitivity analysis ; Studies</subject><ispartof>Journal of clinical epidemiology, 2014-08, Vol.67 (8), p.932-939</ispartof><rights>Elsevier Inc.</rights><rights>2014 Elsevier Inc.</rights><rights>2015 INIST-CNRS</rights><rights>Copyright © 2014 Elsevier Inc. All rights reserved.</rights><rights>Copyright Elsevier Limited Aug 2014</rights><lds50>peer_reviewed</lds50><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-c580t-4a87e0e68f03549da02e4abb2153cc0e6636da460f82e75bcdf2b7a16bd95b293</citedby><cites>FETCH-LOGICAL-c580t-4a87e0e68f03549da02e4abb2153cc0e6636da460f82e75bcdf2b7a16bd95b293</cites></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><linktohtml>$$Uhttps://www.sciencedirect.com/science/article/pii/S0895435614000821$$EHTML$$P50$$Gelsevier$$H</linktohtml><link.rule.ids>314,776,780,3537,27903,27904,65309</link.rule.ids><backlink>$$Uhttp://pascal-francis.inist.fr/vibad/index.php?action=getRecordDetail&idt=28663829$$DView record in Pascal Francis$$Hfree_for_read</backlink><backlink>$$Uhttps://www.ncbi.nlm.nih.gov/pubmed/24774469$$D View this record in MEDLINE/PubMed$$Hfree_for_read</backlink></links><search><creatorcontrib>Zhang, Zhongheng</creatorcontrib><creatorcontrib>Ni, Hongying</creatorcontrib><creatorcontrib>Xu, Xiao</creatorcontrib><title>Observational studies using propensity score analysis underestimated the effect sizes in critical care medicine</title><title>Journal of clinical epidemiology</title><addtitle>J Clin Epidemiol</addtitle><description>Abstract Background and Objective Propensity score (PS) analysis has been increasingly used in critical care medicine; however, its validation has not been systematically investigated. The present study aimed to compare effect sizes in PS-based observational studies vs. randomized controlled trials (RCTs) (or meta-analysis of RCTs). Methods Critical care observational studies using PS were systematically searched in PubMed from inception to April 2013. Identified PS-based studies were matched to one or more RCTs in terms of population, intervention, comparison, and outcome. The effect sizes of experimental treatments were compared for PS-based studies vs. RCTs (or meta-analysis of RCTs) with sign test. Furthermore, ratio of odds ratio (ROR) was calculated from the interaction term of treatment × study type in a logistic regression model. A ROR < 1 indicates greater benefit for experimental treatment in RCTs compared with PS-based studies. RORs of each comparison were pooled by using meta-analytic approach with random-effects model. Results A total of 20 PS-based studies were identified and matched to RCTs. Twelve of the 20 comparisons showed greater beneficial effect for experimental treatment in RCTs than that in PS-based studies (sign test P = 0.503). The difference was statistically significant in four comparisons. ROR can be calculated from 13 comparisons, of which four showed significantly greater beneficial effect for experimental treatment in RCTs. The pooled ROR was 0.71 (95% CI: 0.63, 0.79; P = 0.002), suggesting that RCTs (or meta-analysis of RCTs) were more likely to report beneficial effect for the experimental treatment than PS-based studies. The result remained unchanged in sensitivity analysis and meta-regression. Conclusion In critical care literature, PS-based observational study is likely to report less beneficial effect of experimental treatment compared with RCTs (or meta-analysis of RCTs).</description><subject>Analysis. Health state</subject><subject>Biological and medical sciences</subject><subject>Clinical trials</subject><subject>Confidence intervals</subject><subject>Critical care</subject><subject>Critical Care - methods</subject><subject>Drug therapy</subject><subject>Effect size</subject><subject>Epidemiology</subject><subject>General aspects</subject><subject>Humans</subject><subject>Intensive care</subject><subject>Internal Medicine</subject><subject>Intervention</subject><subject>Logistic Models</subject><subject>Medical sciences</subject><subject>Medicine</subject><subject>Meta-analysis</subject><subject>Meta-Analysis as Topic</subject><subject>Mortality</subject><subject>Observational studies</subject><subject>Observational Studies as Topic - methods</subject><subject>Observational Studies as Topic - standards</subject><subject>Observational study</subject><subject>Odds Ratio</subject><subject>Propensity Score</subject><subject>Public health. Hygiene</subject><subject>Public health. Hygiene-occupational medicine</subject><subject>Randomized controlled trial</subject><subject>Randomized Controlled Trials as Topic - methods</subject><subject>Randomized Controlled Trials as Topic - standards</subject><subject>Ratio of odds ratio</subject><subject>Reproducibility of Results</subject><subject>Research Design</subject><subject>Sensitivity analysis</subject><subject>Studies</subject><issn>0895-4356</issn><issn>1878-5921</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>2014</creationdate><recordtype>article</recordtype><sourceid>EIF</sourceid><sourceid>8G5</sourceid><sourceid>BENPR</sourceid><sourceid>GUQSH</sourceid><sourceid>M2O</sourceid><recordid>eNqNkkFv1DAQhSMEotvCX6giISQuu4wd23EuiKqigFSpB-BsOc4EHLLJ4kkqLb-eSXdLpV7g5IO_9zTz3mTZuYCNAGHedpsu9HHAXdxIEGoDcgPCPslWwpZ2rSspnmYrsJVeq0Kbk-yUqAMQJZT6eXYiVVkqZapVNt7UhOnWT3EcfJ_TNDcRKZ8pDt_zXRp3OFCc9jmFMWHumdlT5P-hwYQ0xa2fsMmnH5hj22KYcoq_WR-HPKQ4xcCewbNyi00MPO-L7Fnre8KXx_cs-3b14evlp_X1zcfPlxfX66AtTGvlbYmAxrZQaFU1HiQqX9dS6CIE_jCFabwy0FqJpa5D08q69MLUTaVrWRVn2ZuDL-_wa-ZJ3TZSwL73A44zOaFVaXUhjP4PtKg4K1MAo68eod04Jw7ljjLCgCgsU-ZAhTQSJWzdLnFQae8EuKU917n79tzSngPpuD0Wnh_t55oD-yu7r4uB10fAE0fbJj-ESA-c5Vzs3fbvDxxyxLcRk6MQcQhcQuKSXDPGf8_y7pHFQi2F_sQ90sPejljgviy3tpyaUABgpSj-AHar0c0</recordid><startdate>20140801</startdate><enddate>20140801</enddate><creator>Zhang, Zhongheng</creator><creator>Ni, Hongying</creator><creator>Xu, Xiao</creator><general>Elsevier Inc</general><general>Elsevier</general><general>Elsevier Limited</general><scope>IQODW</scope><scope>CGR</scope><scope>CUY</scope><scope>CVF</scope><scope>ECM</scope><scope>EIF</scope><scope>NPM</scope><scope>AAYXX</scope><scope>CITATION</scope><scope>3V.</scope><scope>7QL</scope><scope>7QP</scope><scope>7RV</scope><scope>7T2</scope><scope>7T7</scope><scope>7TK</scope><scope>7U7</scope><scope>7U9</scope><scope>7X7</scope><scope>7XB</scope><scope>88C</scope><scope>88E</scope><scope>8AO</scope><scope>8C1</scope><scope>8FD</scope><scope>8FI</scope><scope>8FJ</scope><scope>8FK</scope><scope>8G5</scope><scope>ABUWG</scope><scope>AEUYN</scope><scope>AFKRA</scope><scope>AZQEC</scope><scope>BENPR</scope><scope>C1K</scope><scope>CCPQU</scope><scope>DWQXO</scope><scope>FR3</scope><scope>FYUFA</scope><scope>GHDGH</scope><scope>GNUQQ</scope><scope>GUQSH</scope><scope>H94</scope><scope>K9.</scope><scope>KB0</scope><scope>M0S</scope><scope>M0T</scope><scope>M1P</scope><scope>M2O</scope><scope>M7N</scope><scope>MBDVC</scope><scope>NAPCQ</scope><scope>P64</scope><scope>PQEST</scope><scope>PQQKQ</scope><scope>PQUKI</scope><scope>Q9U</scope><scope>7X8</scope><scope>7U2</scope></search><sort><creationdate>20140801</creationdate><title>Observational studies using propensity score analysis underestimated the effect sizes in critical care medicine</title><author>Zhang, Zhongheng ; Ni, Hongying ; Xu, Xiao</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-c580t-4a87e0e68f03549da02e4abb2153cc0e6636da460f82e75bcdf2b7a16bd95b293</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>2014</creationdate><topic>Analysis. Health state</topic><topic>Biological and medical sciences</topic><topic>Clinical trials</topic><topic>Confidence intervals</topic><topic>Critical care</topic><topic>Critical Care - methods</topic><topic>Drug therapy</topic><topic>Effect size</topic><topic>Epidemiology</topic><topic>General aspects</topic><topic>Humans</topic><topic>Intensive care</topic><topic>Internal Medicine</topic><topic>Intervention</topic><topic>Logistic Models</topic><topic>Medical sciences</topic><topic>Medicine</topic><topic>Meta-analysis</topic><topic>Meta-Analysis as Topic</topic><topic>Mortality</topic><topic>Observational studies</topic><topic>Observational Studies as Topic - methods</topic><topic>Observational Studies as Topic - standards</topic><topic>Observational study</topic><topic>Odds Ratio</topic><topic>Propensity Score</topic><topic>Public health. Hygiene</topic><topic>Public health. Hygiene-occupational medicine</topic><topic>Randomized controlled trial</topic><topic>Randomized Controlled Trials as Topic - methods</topic><topic>Randomized Controlled Trials as Topic - standards</topic><topic>Ratio of odds ratio</topic><topic>Reproducibility of Results</topic><topic>Research Design</topic><topic>Sensitivity analysis</topic><topic>Studies</topic><toplevel>peer_reviewed</toplevel><toplevel>online_resources</toplevel><creatorcontrib>Zhang, Zhongheng</creatorcontrib><creatorcontrib>Ni, Hongying</creatorcontrib><creatorcontrib>Xu, Xiao</creatorcontrib><collection>Pascal-Francis</collection><collection>Medline</collection><collection>MEDLINE</collection><collection>MEDLINE (Ovid)</collection><collection>MEDLINE</collection><collection>MEDLINE</collection><collection>PubMed</collection><collection>CrossRef</collection><collection>ProQuest Central (Corporate)</collection><collection>Bacteriology Abstracts (Microbiology B)</collection><collection>Calcium & Calcified Tissue Abstracts</collection><collection>Nursing & Allied Health Database</collection><collection>Health and Safety Science Abstracts (Full archive)</collection><collection>Industrial and Applied Microbiology Abstracts (Microbiology A)</collection><collection>Neurosciences Abstracts</collection><collection>Toxicology Abstracts</collection><collection>Virology and AIDS Abstracts</collection><collection>Health & Medical Collection</collection><collection>ProQuest Central (purchase pre-March 2016)</collection><collection>Healthcare Administration Database (Alumni)</collection><collection>Medical Database (Alumni Edition)</collection><collection>ProQuest Pharma Collection</collection><collection>Public Health Database</collection><collection>Technology Research Database</collection><collection>Hospital Premium Collection</collection><collection>Hospital Premium Collection (Alumni Edition)</collection><collection>ProQuest Central (Alumni) (purchase pre-March 2016)</collection><collection>Research Library (Alumni Edition)</collection><collection>ProQuest Central (Alumni Edition)</collection><collection>ProQuest One Sustainability</collection><collection>ProQuest Central UK/Ireland</collection><collection>ProQuest Central Essentials</collection><collection>ProQuest Central</collection><collection>Environmental Sciences and Pollution Management</collection><collection>ProQuest One Community College</collection><collection>ProQuest Central Korea</collection><collection>Engineering Research Database</collection><collection>Health Research Premium Collection</collection><collection>Health Research Premium Collection (Alumni)</collection><collection>ProQuest Central Student</collection><collection>Research Library Prep</collection><collection>AIDS and Cancer Research Abstracts</collection><collection>ProQuest Health & Medical Complete (Alumni)</collection><collection>Nursing & Allied Health Database (Alumni Edition)</collection><collection>Health & Medical Collection (Alumni Edition)</collection><collection>Healthcare Administration Database</collection><collection>Medical Database</collection><collection>Research Library</collection><collection>Algology Mycology and Protozoology Abstracts (Microbiology C)</collection><collection>Research Library (Corporate)</collection><collection>Nursing & Allied Health Premium</collection><collection>Biotechnology and BioEngineering Abstracts</collection><collection>ProQuest One Academic Eastern Edition (DO NOT USE)</collection><collection>ProQuest One Academic</collection><collection>ProQuest One Academic UKI Edition</collection><collection>ProQuest Central Basic</collection><collection>MEDLINE - Academic</collection><collection>Safety Science and Risk</collection><jtitle>Journal of clinical epidemiology</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>Zhang, Zhongheng</au><au>Ni, Hongying</au><au>Xu, Xiao</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>Observational studies using propensity score analysis underestimated the effect sizes in critical care medicine</atitle><jtitle>Journal of clinical epidemiology</jtitle><addtitle>J Clin Epidemiol</addtitle><date>2014-08-01</date><risdate>2014</risdate><volume>67</volume><issue>8</issue><spage>932</spage><epage>939</epage><pages>932-939</pages><issn>0895-4356</issn><eissn>1878-5921</eissn><abstract>Abstract Background and Objective Propensity score (PS) analysis has been increasingly used in critical care medicine; however, its validation has not been systematically investigated. The present study aimed to compare effect sizes in PS-based observational studies vs. randomized controlled trials (RCTs) (or meta-analysis of RCTs). Methods Critical care observational studies using PS were systematically searched in PubMed from inception to April 2013. Identified PS-based studies were matched to one or more RCTs in terms of population, intervention, comparison, and outcome. The effect sizes of experimental treatments were compared for PS-based studies vs. RCTs (or meta-analysis of RCTs) with sign test. Furthermore, ratio of odds ratio (ROR) was calculated from the interaction term of treatment × study type in a logistic regression model. A ROR < 1 indicates greater benefit for experimental treatment in RCTs compared with PS-based studies. RORs of each comparison were pooled by using meta-analytic approach with random-effects model. Results A total of 20 PS-based studies were identified and matched to RCTs. Twelve of the 20 comparisons showed greater beneficial effect for experimental treatment in RCTs than that in PS-based studies (sign test P = 0.503). The difference was statistically significant in four comparisons. ROR can be calculated from 13 comparisons, of which four showed significantly greater beneficial effect for experimental treatment in RCTs. The pooled ROR was 0.71 (95% CI: 0.63, 0.79; P = 0.002), suggesting that RCTs (or meta-analysis of RCTs) were more likely to report beneficial effect for the experimental treatment than PS-based studies. The result remained unchanged in sensitivity analysis and meta-regression. Conclusion In critical care literature, PS-based observational study is likely to report less beneficial effect of experimental treatment compared with RCTs (or meta-analysis of RCTs).</abstract><cop>New York, NY</cop><pub>Elsevier Inc</pub><pmid>24774469</pmid><doi>10.1016/j.jclinepi.2014.02.018</doi><tpages>8</tpages></addata></record> |
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| subjects | Analysis. Health state Biological and medical sciences Clinical trials Confidence intervals Critical care Critical Care - methods Drug therapy Effect size Epidemiology General aspects Humans Intensive care Internal Medicine Intervention Logistic Models Medical sciences Medicine Meta-analysis Meta-Analysis as Topic Mortality Observational studies Observational Studies as Topic - methods Observational Studies as Topic - standards Observational study Odds Ratio Propensity Score Public health. Hygiene Public health. Hygiene-occupational medicine Randomized controlled trial Randomized Controlled Trials as Topic - methods Randomized Controlled Trials as Topic - standards Ratio of odds ratio Reproducibility of Results Research Design Sensitivity analysis Studies |
| title | Observational studies using propensity score analysis underestimated the effect sizes in critical care medicine |
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