Volunteer bias in recruitment, retention, and blood sample donation in a randomised controlled trial involving mothers and their children at six months and two years: a longitudinal analysis
The vulnerability of clinical trials to volunteer bias is under-reported. Volunteer bias is systematic error due to differences between those who choose to participate in studies and those who do not. This paper extends the applications of the concept of volunteer bias by using data from a trial of...
Gespeichert in:
| Veröffentlicht in: | PloS one 2013-07, Vol.8 (7), p.e67912-e67912 |
|---|---|
| Hauptverfasser: | , , , , , , , , , , , |
| Format: | Artikel |
| Sprache: | eng |
| Schlagworte: | |
| Online-Zugang: | Volltext |
| Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
| container_end_page | e67912 |
|---|---|
| container_issue | 7 |
| container_start_page | e67912 |
| container_title | PloS one |
| container_volume | 8 |
| creator | Jordan, Sue Watkins, Alan Storey, Mel Allen, Steven J Brooks, Caroline J Garaiova, Iveta Heaven, Martin L Jones, Ruth Plummer, Sue F Russell, Ian T Thornton, Catherine A Morgan, Gareth |
| description | The vulnerability of clinical trials to volunteer bias is under-reported. Volunteer bias is systematic error due to differences between those who choose to participate in studies and those who do not.
This paper extends the applications of the concept of volunteer bias by using data from a trial of probiotic supplementation for childhood atopy in healthy dyads to explore 1) differences between a) trial participants and aggregated data from publicly available databases b) participants and non-participants as the trial progressed 2) impact on trial findings of weighting data according to deprivation (Townsend) fifths in the sample and target populations. 1) a) Recruits (n = 454) were less deprived than the target population, matched for area of residence and delivery dates (n = 6,893) (mean [SD] deprivation scores 0.09[4.21] and 0.79[4.08], t = 3.44, df = 511, p |
| doi_str_mv | 10.1371/journal.pone.0067912 |
| format | Article |
| fullrecord | <record><control><sourceid>gale_plos_</sourceid><recordid>TN_cdi_plos_journals_1974582246</recordid><sourceformat>XML</sourceformat><sourcesystem>PC</sourcesystem><galeid>A478358029</galeid><doaj_id>oai_doaj_org_article_a9f2d049da614644b8d4c23bb86c36f6</doaj_id><sourcerecordid>A478358029</sourcerecordid><originalsourceid>FETCH-LOGICAL-c692t-adcc46dfd04116355b2b13fa03a325d1b817ab6c4294ccc6d39c23f0ecc0c5d73</originalsourceid><addsrcrecordid>eNqNk9tq3DAQhk1padK0b1BaQ6G0kN3qZNnuRSGEHgKBQA-5FbIk7yrI0kaS0-Tl-mwdJ07IllwUX0jWfPOPZjRTFC8xWmJa4w9nYYxeuuUmeLNEiNctJo-KXdxSsuAE0cf39jvFs5TOEKpow_nTYofQpmaMV7vFn9PgRp-NiWVnZSqtL6NRcbR5MD7vw0-G1Qa_X0qvy86FoMskh40zpQ5eTqbJSZYR7GGwyehSBZ9jcA62OVrpALgI7sL6VTmEvDYxXYvBzsZSra3T0YBELpO9BMLn9Qz8DuWVkTF9BH0X_MrmUVtIGqzSXSWbnhdPeumSeTGve8WvL59_Hn5bHJ98PTo8OF4o3pK8kFopxnWvEcOY06rqSIdpLxGVlFQadw2uZccVIy1TSnFNW0Voj4xSSFW6pnvF6xvdjQtJzKVPArc1qxpCGAfi6IbQQZ6JTbSDjFciSCuuD0JcCRmzVc4I2fYEbtJqyTHjjHWNZhCu6xquKO8nrU9ztLEbjFbwAlG6LdFti7drsQoXgtYI9BoQeDcLxHA-mpQFPIwyzklvwgj3vi4DpdWU2Zt_0Iezm6mVhASs7wPEVZOoOGB1Q6sGkRao5QMUfNoMFprC9BbOtxzebzlMjWMu80qOKYmjH9__nz053Wbf3mPXRjpoKWj0qVvTNshuQBVDStH0d0XGSExjdlsNMY2ZmMcM3F7df6A7p9u5on8BZa0neQ</addsrcrecordid><sourcetype>Open Website</sourcetype><iscdi>true</iscdi><recordtype>article</recordtype><pqid>1974582246</pqid></control><display><type>article</type><title>Volunteer bias in recruitment, retention, and blood sample donation in a randomised controlled trial involving mothers and their children at six months and two years: a longitudinal analysis</title><source>MEDLINE</source><source>DOAJ Directory of Open Access Journals</source><source>EZB-FREE-00999 freely available EZB journals</source><source>PubMed Central</source><source>Free Full-Text Journals in Chemistry</source><source>Public Library of Science (PLoS)</source><creator>Jordan, Sue ; Watkins, Alan ; Storey, Mel ; Allen, Steven J ; Brooks, Caroline J ; Garaiova, Iveta ; Heaven, Martin L ; Jones, Ruth ; Plummer, Sue F ; Russell, Ian T ; Thornton, Catherine A ; Morgan, Gareth</creator><creatorcontrib>Jordan, Sue ; Watkins, Alan ; Storey, Mel ; Allen, Steven J ; Brooks, Caroline J ; Garaiova, Iveta ; Heaven, Martin L ; Jones, Ruth ; Plummer, Sue F ; Russell, Ian T ; Thornton, Catherine A ; Morgan, Gareth</creatorcontrib><description>The vulnerability of clinical trials to volunteer bias is under-reported. Volunteer bias is systematic error due to differences between those who choose to participate in studies and those who do not.
This paper extends the applications of the concept of volunteer bias by using data from a trial of probiotic supplementation for childhood atopy in healthy dyads to explore 1) differences between a) trial participants and aggregated data from publicly available databases b) participants and non-participants as the trial progressed 2) impact on trial findings of weighting data according to deprivation (Townsend) fifths in the sample and target populations. 1) a) Recruits (n = 454) were less deprived than the target population, matched for area of residence and delivery dates (n = 6,893) (mean [SD] deprivation scores 0.09[4.21] and 0.79[4.08], t = 3.44, df = 511, p<0.001). b) i) As the trial progressed, representation of the most deprived decreased. These participants and smokers were less likely to be retained at 6 months (n = 430[95%]) (OR 0.29,0.13-0.67 and 0.20,0.09-0.46), and 2 years (n = 380[84%]) (aOR 0.68,0.50-0.93 and 0.55,0.28-1.09), and consent to infant blood sample donation (n = 220[48%]) (aOR 0.72,0.57-0.92 and 0.43,0.22-0.83). ii) Mothers interested in probiotics or research or reporting infants' adverse events or rashes were more likely to attend research clinics and consent to skin-prick testing. Mothers participating to help children were more likely to consent to infant blood sample donation. 2) In one trial outcome, atopic eczema, the intervention had a positive effect only in the over-represented, least deprived group. Here, data weighting attenuated risk reduction from 6.9%(0.9-13.1%) to 4.6%(-1.4-+10.5%), and OR from 0.40(0.18-0.91) to 0.56(0.26-1.21). Other findings were unchanged.
Potential for volunteer bias intensified during the trial, due to non-participation of the most deprived and smokers. However, these were not the only predictors of non-participation. Data weighting quantified volunteer bias and modified one important trial outcome.
This randomised, double blind, parallel group, placebo controlled trial is registered with the International Standard Randomised Controlled Trials Register, Number (ISRCTN) 26287422. Registered title: Probiotics in the prevention of atopy in infants and children.</description><identifier>ISSN: 1932-6203</identifier><identifier>EISSN: 1932-6203</identifier><identifier>DOI: 10.1371/journal.pone.0067912</identifier><identifier>PMID: 23874465</identifier><language>eng</language><publisher>United States: Public Library of Science</publisher><subject>Adult ; Altruism ; Analysis ; Asthma ; Atopy ; Bias ; Blood ; Child, Preschool ; Children ; Clinical trials ; Consent ; Demographics ; Deprivation ; Eczema ; Ethics ; Female ; Gifts ; Humans ; Infant ; Infants ; Longitudinal Studies ; Male ; Medical research ; Medicine ; Mothers ; Outcome and Process Assessment, Health Care ; Pregnancy ; Probiotics ; Product development ; Randomization ; Randomized Controlled Trials as Topic ; Research Design ; Retention ; Risk Factors ; Risk reduction ; Science Policy ; Selection Bias ; Skin diseases ; Skin tests ; Smoking ; Sociodemographics ; Studies ; Supplements ; Systematic review ; Validity ; Volunteers ; Weighting ; Womens health</subject><ispartof>PloS one, 2013-07, Vol.8 (7), p.e67912-e67912</ispartof><rights>COPYRIGHT 2013 Public Library of Science</rights><rights>2013 Jordan et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License: https://creativecommons.org/licenses/by/4.0/ (the “License”), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.</rights><rights>2013 Jordan et al 2013 Jordan et al</rights><lds50>peer_reviewed</lds50><oa>free_for_read</oa><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-c692t-adcc46dfd04116355b2b13fa03a325d1b817ab6c4294ccc6d39c23f0ecc0c5d73</citedby><cites>FETCH-LOGICAL-c692t-adcc46dfd04116355b2b13fa03a325d1b817ab6c4294ccc6d39c23f0ecc0c5d73</cites></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><linktopdf>$$Uhttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC3706448/pdf/$$EPDF$$P50$$Gpubmedcentral$$Hfree_for_read</linktopdf><linktohtml>$$Uhttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC3706448/$$EHTML$$P50$$Gpubmedcentral$$Hfree_for_read</linktohtml><link.rule.ids>230,314,723,776,780,860,881,2096,2915,23845,27901,27902,53766,53768,79342,79343</link.rule.ids><backlink>$$Uhttps://www.ncbi.nlm.nih.gov/pubmed/23874465$$D View this record in MEDLINE/PubMed$$Hfree_for_read</backlink></links><search><creatorcontrib>Jordan, Sue</creatorcontrib><creatorcontrib>Watkins, Alan</creatorcontrib><creatorcontrib>Storey, Mel</creatorcontrib><creatorcontrib>Allen, Steven J</creatorcontrib><creatorcontrib>Brooks, Caroline J</creatorcontrib><creatorcontrib>Garaiova, Iveta</creatorcontrib><creatorcontrib>Heaven, Martin L</creatorcontrib><creatorcontrib>Jones, Ruth</creatorcontrib><creatorcontrib>Plummer, Sue F</creatorcontrib><creatorcontrib>Russell, Ian T</creatorcontrib><creatorcontrib>Thornton, Catherine A</creatorcontrib><creatorcontrib>Morgan, Gareth</creatorcontrib><title>Volunteer bias in recruitment, retention, and blood sample donation in a randomised controlled trial involving mothers and their children at six months and two years: a longitudinal analysis</title><title>PloS one</title><addtitle>PLoS One</addtitle><description>The vulnerability of clinical trials to volunteer bias is under-reported. Volunteer bias is systematic error due to differences between those who choose to participate in studies and those who do not.
This paper extends the applications of the concept of volunteer bias by using data from a trial of probiotic supplementation for childhood atopy in healthy dyads to explore 1) differences between a) trial participants and aggregated data from publicly available databases b) participants and non-participants as the trial progressed 2) impact on trial findings of weighting data according to deprivation (Townsend) fifths in the sample and target populations. 1) a) Recruits (n = 454) were less deprived than the target population, matched for area of residence and delivery dates (n = 6,893) (mean [SD] deprivation scores 0.09[4.21] and 0.79[4.08], t = 3.44, df = 511, p<0.001). b) i) As the trial progressed, representation of the most deprived decreased. These participants and smokers were less likely to be retained at 6 months (n = 430[95%]) (OR 0.29,0.13-0.67 and 0.20,0.09-0.46), and 2 years (n = 380[84%]) (aOR 0.68,0.50-0.93 and 0.55,0.28-1.09), and consent to infant blood sample donation (n = 220[48%]) (aOR 0.72,0.57-0.92 and 0.43,0.22-0.83). ii) Mothers interested in probiotics or research or reporting infants' adverse events or rashes were more likely to attend research clinics and consent to skin-prick testing. Mothers participating to help children were more likely to consent to infant blood sample donation. 2) In one trial outcome, atopic eczema, the intervention had a positive effect only in the over-represented, least deprived group. Here, data weighting attenuated risk reduction from 6.9%(0.9-13.1%) to 4.6%(-1.4-+10.5%), and OR from 0.40(0.18-0.91) to 0.56(0.26-1.21). Other findings were unchanged.
Potential for volunteer bias intensified during the trial, due to non-participation of the most deprived and smokers. However, these were not the only predictors of non-participation. Data weighting quantified volunteer bias and modified one important trial outcome.
This randomised, double blind, parallel group, placebo controlled trial is registered with the International Standard Randomised Controlled Trials Register, Number (ISRCTN) 26287422. Registered title: Probiotics in the prevention of atopy in infants and children.</description><subject>Adult</subject><subject>Altruism</subject><subject>Analysis</subject><subject>Asthma</subject><subject>Atopy</subject><subject>Bias</subject><subject>Blood</subject><subject>Child, Preschool</subject><subject>Children</subject><subject>Clinical trials</subject><subject>Consent</subject><subject>Demographics</subject><subject>Deprivation</subject><subject>Eczema</subject><subject>Ethics</subject><subject>Female</subject><subject>Gifts</subject><subject>Humans</subject><subject>Infant</subject><subject>Infants</subject><subject>Longitudinal Studies</subject><subject>Male</subject><subject>Medical research</subject><subject>Medicine</subject><subject>Mothers</subject><subject>Outcome and Process Assessment, Health Care</subject><subject>Pregnancy</subject><subject>Probiotics</subject><subject>Product development</subject><subject>Randomization</subject><subject>Randomized Controlled Trials as Topic</subject><subject>Research Design</subject><subject>Retention</subject><subject>Risk Factors</subject><subject>Risk reduction</subject><subject>Science Policy</subject><subject>Selection Bias</subject><subject>Skin diseases</subject><subject>Skin tests</subject><subject>Smoking</subject><subject>Sociodemographics</subject><subject>Studies</subject><subject>Supplements</subject><subject>Systematic review</subject><subject>Validity</subject><subject>Volunteers</subject><subject>Weighting</subject><subject>Womens health</subject><issn>1932-6203</issn><issn>1932-6203</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>2013</creationdate><recordtype>article</recordtype><sourceid>EIF</sourceid><sourceid>BENPR</sourceid><sourceid>DOA</sourceid><recordid>eNqNk9tq3DAQhk1padK0b1BaQ6G0kN3qZNnuRSGEHgKBQA-5FbIk7yrI0kaS0-Tl-mwdJ07IllwUX0jWfPOPZjRTFC8xWmJa4w9nYYxeuuUmeLNEiNctJo-KXdxSsuAE0cf39jvFs5TOEKpow_nTYofQpmaMV7vFn9PgRp-NiWVnZSqtL6NRcbR5MD7vw0-G1Qa_X0qvy86FoMskh40zpQ5eTqbJSZYR7GGwyehSBZ9jcA62OVrpALgI7sL6VTmEvDYxXYvBzsZSra3T0YBELpO9BMLn9Qz8DuWVkTF9BH0X_MrmUVtIGqzSXSWbnhdPeumSeTGve8WvL59_Hn5bHJ98PTo8OF4o3pK8kFopxnWvEcOY06rqSIdpLxGVlFQadw2uZccVIy1TSnFNW0Voj4xSSFW6pnvF6xvdjQtJzKVPArc1qxpCGAfi6IbQQZ6JTbSDjFciSCuuD0JcCRmzVc4I2fYEbtJqyTHjjHWNZhCu6xquKO8nrU9ztLEbjFbwAlG6LdFti7drsQoXgtYI9BoQeDcLxHA-mpQFPIwyzklvwgj3vi4DpdWU2Zt_0Iezm6mVhASs7wPEVZOoOGB1Q6sGkRao5QMUfNoMFprC9BbOtxzebzlMjWMu80qOKYmjH9__nz053Wbf3mPXRjpoKWj0qVvTNshuQBVDStH0d0XGSExjdlsNMY2ZmMcM3F7df6A7p9u5on8BZa0neQ</recordid><startdate>20130709</startdate><enddate>20130709</enddate><creator>Jordan, Sue</creator><creator>Watkins, Alan</creator><creator>Storey, Mel</creator><creator>Allen, Steven J</creator><creator>Brooks, Caroline J</creator><creator>Garaiova, Iveta</creator><creator>Heaven, Martin L</creator><creator>Jones, Ruth</creator><creator>Plummer, Sue F</creator><creator>Russell, Ian T</creator><creator>Thornton, Catherine A</creator><creator>Morgan, Gareth</creator><general>Public Library of Science</general><general>Public Library of Science (PLoS)</general><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>IOV</scope><scope>ISR</scope><scope>3V.</scope><scope>7QG</scope><scope>7QL</scope><scope>7QO</scope><scope>7RV</scope><scope>7SN</scope><scope>7SS</scope><scope>7T5</scope><scope>7TG</scope><scope>7TM</scope><scope>7U9</scope><scope>7X2</scope><scope>7X7</scope><scope>7XB</scope><scope>88E</scope><scope>8AO</scope><scope>8C1</scope><scope>8FD</scope><scope>8FE</scope><scope>8FG</scope><scope>8FH</scope><scope>8FI</scope><scope>8FJ</scope><scope>8FK</scope><scope>ABJCF</scope><scope>ABUWG</scope><scope>AEUYN</scope><scope>AFKRA</scope><scope>ARAPS</scope><scope>ATCPS</scope><scope>AZQEC</scope><scope>BBNVY</scope><scope>BENPR</scope><scope>BGLVJ</scope><scope>BHPHI</scope><scope>C1K</scope><scope>CCPQU</scope><scope>D1I</scope><scope>DWQXO</scope><scope>FR3</scope><scope>FYUFA</scope><scope>GHDGH</scope><scope>GNUQQ</scope><scope>H94</scope><scope>HCIFZ</scope><scope>K9.</scope><scope>KB.</scope><scope>KB0</scope><scope>KL.</scope><scope>L6V</scope><scope>LK8</scope><scope>M0K</scope><scope>M0S</scope><scope>M1P</scope><scope>M7N</scope><scope>M7P</scope><scope>M7S</scope><scope>NAPCQ</scope><scope>P5Z</scope><scope>P62</scope><scope>P64</scope><scope>PATMY</scope><scope>PDBOC</scope><scope>PIMPY</scope><scope>PQEST</scope><scope>PQQKQ</scope><scope>PQUKI</scope><scope>PRINS</scope><scope>PTHSS</scope><scope>PYCSY</scope><scope>RC3</scope><scope>7X8</scope><scope>5PM</scope><scope>DOA</scope></search><sort><creationdate>20130709</creationdate><title>Volunteer bias in recruitment, retention, and blood sample donation in a randomised controlled trial involving mothers and their children at six months and two years: a longitudinal analysis</title><author>Jordan, Sue ; Watkins, Alan ; Storey, Mel ; Allen, Steven J ; Brooks, Caroline J ; Garaiova, Iveta ; Heaven, Martin L ; Jones, Ruth ; Plummer, Sue F ; Russell, Ian T ; Thornton, Catherine A ; Morgan, Gareth</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-c692t-adcc46dfd04116355b2b13fa03a325d1b817ab6c4294ccc6d39c23f0ecc0c5d73</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>2013</creationdate><topic>Adult</topic><topic>Altruism</topic><topic>Analysis</topic><topic>Asthma</topic><topic>Atopy</topic><topic>Bias</topic><topic>Blood</topic><topic>Child, Preschool</topic><topic>Children</topic><topic>Clinical trials</topic><topic>Consent</topic><topic>Demographics</topic><topic>Deprivation</topic><topic>Eczema</topic><topic>Ethics</topic><topic>Female</topic><topic>Gifts</topic><topic>Humans</topic><topic>Infant</topic><topic>Infants</topic><topic>Longitudinal Studies</topic><topic>Male</topic><topic>Medical research</topic><topic>Medicine</topic><topic>Mothers</topic><topic>Outcome and Process Assessment, Health Care</topic><topic>Pregnancy</topic><topic>Probiotics</topic><topic>Product development</topic><topic>Randomization</topic><topic>Randomized Controlled Trials as Topic</topic><topic>Research Design</topic><topic>Retention</topic><topic>Risk Factors</topic><topic>Risk reduction</topic><topic>Science Policy</topic><topic>Selection Bias</topic><topic>Skin diseases</topic><topic>Skin tests</topic><topic>Smoking</topic><topic>Sociodemographics</topic><topic>Studies</topic><topic>Supplements</topic><topic>Systematic review</topic><topic>Validity</topic><topic>Volunteers</topic><topic>Weighting</topic><topic>Womens health</topic><toplevel>peer_reviewed</toplevel><toplevel>online_resources</toplevel><creatorcontrib>Jordan, Sue</creatorcontrib><creatorcontrib>Watkins, Alan</creatorcontrib><creatorcontrib>Storey, Mel</creatorcontrib><creatorcontrib>Allen, Steven J</creatorcontrib><creatorcontrib>Brooks, Caroline J</creatorcontrib><creatorcontrib>Garaiova, Iveta</creatorcontrib><creatorcontrib>Heaven, Martin L</creatorcontrib><creatorcontrib>Jones, Ruth</creatorcontrib><creatorcontrib>Plummer, Sue F</creatorcontrib><creatorcontrib>Russell, Ian T</creatorcontrib><creatorcontrib>Thornton, Catherine A</creatorcontrib><creatorcontrib>Morgan, Gareth</creatorcontrib><collection>Medline</collection><collection>MEDLINE</collection><collection>MEDLINE (Ovid)</collection><collection>MEDLINE</collection><collection>MEDLINE</collection><collection>PubMed</collection><collection>CrossRef</collection><collection>Gale In Context: Opposing Viewpoints</collection><collection>Gale In Context: Science</collection><collection>ProQuest Central (Corporate)</collection><collection>Animal Behavior Abstracts</collection><collection>Bacteriology Abstracts (Microbiology B)</collection><collection>Biotechnology Research Abstracts</collection><collection>Nursing & Allied Health Database</collection><collection>Ecology Abstracts</collection><collection>Entomology Abstracts (Full archive)</collection><collection>Immunology Abstracts</collection><collection>Meteorological & Geoastrophysical Abstracts</collection><collection>Nucleic Acids Abstracts</collection><collection>Virology and AIDS Abstracts</collection><collection>Agricultural Science Collection</collection><collection>Health & Medical Collection</collection><collection>ProQuest Central (purchase pre-March 2016)</collection><collection>Medical Database (Alumni Edition)</collection><collection>ProQuest Pharma Collection</collection><collection>Public Health Database</collection><collection>Technology Research Database</collection><collection>ProQuest SciTech Collection</collection><collection>ProQuest Technology Collection</collection><collection>ProQuest Natural Science Collection</collection><collection>Hospital Premium Collection</collection><collection>Hospital Premium Collection (Alumni Edition)</collection><collection>ProQuest Central (Alumni) (purchase pre-March 2016)</collection><collection>Materials Science & Engineering Collection</collection><collection>ProQuest Central (Alumni Edition)</collection><collection>ProQuest One Sustainability</collection><collection>ProQuest Central UK/Ireland</collection><collection>Advanced Technologies & Aerospace Collection</collection><collection>Agricultural & Environmental Science Collection</collection><collection>ProQuest Central Essentials</collection><collection>Biological Science Collection</collection><collection>ProQuest Central</collection><collection>Technology Collection</collection><collection>Natural Science Collection</collection><collection>Environmental Sciences and Pollution Management</collection><collection>ProQuest One Community College</collection><collection>ProQuest Materials Science Collection</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>AIDS and Cancer Research Abstracts</collection><collection>SciTech Premium Collection</collection><collection>ProQuest Health & Medical Complete (Alumni)</collection><collection>Materials Science Database</collection><collection>Nursing & Allied Health Database (Alumni Edition)</collection><collection>Meteorological & Geoastrophysical Abstracts - Academic</collection><collection>ProQuest Engineering Collection</collection><collection>ProQuest Biological Science Collection</collection><collection>Agricultural Science Database</collection><collection>Health & Medical Collection (Alumni Edition)</collection><collection>Medical Database</collection><collection>Algology Mycology and Protozoology Abstracts (Microbiology C)</collection><collection>Biological Science Database</collection><collection>Engineering Database</collection><collection>Nursing & Allied Health Premium</collection><collection>Advanced Technologies & Aerospace Database</collection><collection>ProQuest Advanced Technologies & Aerospace Collection</collection><collection>Biotechnology and BioEngineering Abstracts</collection><collection>Environmental Science Database</collection><collection>Materials Science Collection</collection><collection>Publicly Available Content Database</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 China</collection><collection>Engineering Collection</collection><collection>Environmental Science Collection</collection><collection>Genetics Abstracts</collection><collection>MEDLINE - Academic</collection><collection>PubMed Central (Full Participant titles)</collection><collection>DOAJ Directory of Open Access Journals</collection><jtitle>PloS one</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>Jordan, Sue</au><au>Watkins, Alan</au><au>Storey, Mel</au><au>Allen, Steven J</au><au>Brooks, Caroline J</au><au>Garaiova, Iveta</au><au>Heaven, Martin L</au><au>Jones, Ruth</au><au>Plummer, Sue F</au><au>Russell, Ian T</au><au>Thornton, Catherine A</au><au>Morgan, Gareth</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>Volunteer bias in recruitment, retention, and blood sample donation in a randomised controlled trial involving mothers and their children at six months and two years: a longitudinal analysis</atitle><jtitle>PloS one</jtitle><addtitle>PLoS One</addtitle><date>2013-07-09</date><risdate>2013</risdate><volume>8</volume><issue>7</issue><spage>e67912</spage><epage>e67912</epage><pages>e67912-e67912</pages><issn>1932-6203</issn><eissn>1932-6203</eissn><abstract>The vulnerability of clinical trials to volunteer bias is under-reported. Volunteer bias is systematic error due to differences between those who choose to participate in studies and those who do not.
This paper extends the applications of the concept of volunteer bias by using data from a trial of probiotic supplementation for childhood atopy in healthy dyads to explore 1) differences between a) trial participants and aggregated data from publicly available databases b) participants and non-participants as the trial progressed 2) impact on trial findings of weighting data according to deprivation (Townsend) fifths in the sample and target populations. 1) a) Recruits (n = 454) were less deprived than the target population, matched for area of residence and delivery dates (n = 6,893) (mean [SD] deprivation scores 0.09[4.21] and 0.79[4.08], t = 3.44, df = 511, p<0.001). b) i) As the trial progressed, representation of the most deprived decreased. These participants and smokers were less likely to be retained at 6 months (n = 430[95%]) (OR 0.29,0.13-0.67 and 0.20,0.09-0.46), and 2 years (n = 380[84%]) (aOR 0.68,0.50-0.93 and 0.55,0.28-1.09), and consent to infant blood sample donation (n = 220[48%]) (aOR 0.72,0.57-0.92 and 0.43,0.22-0.83). ii) Mothers interested in probiotics or research or reporting infants' adverse events or rashes were more likely to attend research clinics and consent to skin-prick testing. Mothers participating to help children were more likely to consent to infant blood sample donation. 2) In one trial outcome, atopic eczema, the intervention had a positive effect only in the over-represented, least deprived group. Here, data weighting attenuated risk reduction from 6.9%(0.9-13.1%) to 4.6%(-1.4-+10.5%), and OR from 0.40(0.18-0.91) to 0.56(0.26-1.21). Other findings were unchanged.
Potential for volunteer bias intensified during the trial, due to non-participation of the most deprived and smokers. However, these were not the only predictors of non-participation. Data weighting quantified volunteer bias and modified one important trial outcome.
This randomised, double blind, parallel group, placebo controlled trial is registered with the International Standard Randomised Controlled Trials Register, Number (ISRCTN) 26287422. Registered title: Probiotics in the prevention of atopy in infants and children.</abstract><cop>United States</cop><pub>Public Library of Science</pub><pmid>23874465</pmid><doi>10.1371/journal.pone.0067912</doi><tpages>e67912</tpages><oa>free_for_read</oa></addata></record> |
| fulltext | fulltext |
| identifier | ISSN: 1932-6203 |
| ispartof | PloS one, 2013-07, Vol.8 (7), p.e67912-e67912 |
| issn | 1932-6203 1932-6203 |
| language | eng |
| recordid | cdi_plos_journals_1974582246 |
| source | MEDLINE; DOAJ Directory of Open Access Journals; EZB-FREE-00999 freely available EZB journals; PubMed Central; Free Full-Text Journals in Chemistry; Public Library of Science (PLoS) |
| subjects | Adult Altruism Analysis Asthma Atopy Bias Blood Child, Preschool Children Clinical trials Consent Demographics Deprivation Eczema Ethics Female Gifts Humans Infant Infants Longitudinal Studies Male Medical research Medicine Mothers Outcome and Process Assessment, Health Care Pregnancy Probiotics Product development Randomization Randomized Controlled Trials as Topic Research Design Retention Risk Factors Risk reduction Science Policy Selection Bias Skin diseases Skin tests Smoking Sociodemographics Studies Supplements Systematic review Validity Volunteers Weighting Womens health |
| title | Volunteer bias in recruitment, retention, and blood sample donation in a randomised controlled trial involving mothers and their children at six months and two years: a longitudinal analysis |
| url | https://sfx.bib-bvb.de/sfx_tum?ctx_ver=Z39.88-2004&ctx_enc=info:ofi/enc:UTF-8&ctx_tim=2025-02-08T09%3A26%3A50IST&url_ver=Z39.88-2004&url_ctx_fmt=infofi/fmt:kev:mtx:ctx&rfr_id=info:sid/primo.exlibrisgroup.com:primo3-Article-gale_plos_&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.genre=article&rft.atitle=Volunteer%20bias%20in%20recruitment,%20retention,%20and%20blood%20sample%20donation%20in%20a%20randomised%20controlled%20trial%20involving%20mothers%20and%20their%20children%20at%20six%20months%20and%20two%20years:%20a%20longitudinal%20analysis&rft.jtitle=PloS%20one&rft.au=Jordan,%20Sue&rft.date=2013-07-09&rft.volume=8&rft.issue=7&rft.spage=e67912&rft.epage=e67912&rft.pages=e67912-e67912&rft.issn=1932-6203&rft.eissn=1932-6203&rft_id=info:doi/10.1371/journal.pone.0067912&rft_dat=%3Cgale_plos_%3EA478358029%3C/gale_plos_%3E%3Curl%3E%3C/url%3E&disable_directlink=true&sfx.directlink=off&sfx.report_link=0&rft_id=info:oai/&rft_pqid=1974582246&rft_id=info:pmid/23874465&rft_galeid=A478358029&rft_doaj_id=oai_doaj_org_article_a9f2d049da614644b8d4c23bb86c36f6&rfr_iscdi=true |