Comparisons of citations in Web of Science, Scopus, and Google Scholar for articles published in general medical journals

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data-ga-label="JAMA"> Search in NLM Catalog </a></li><li><a class="add-to-search-link dropdown-block-link" ref ="linksrc=add_to_search_link" role="button" data-search-term='"JAMA"[jour]' data-ga-category="search" data-ga-action="add_to_search" data-ga-label='"JAMA"[jour]' href="#"> Add to Search </a></li></ul></div></div></div><span class="period">. </span><span class="cit">2009 Sep 9;302(10):1092-6.</span> </div> <span class="citation-doi"> doi: 10.1001/jama.2009.1307. </span> </div> <h1 class="heading-title"> Comparisons of citations in Web of Science, Scopus, and Google Scholar for articles published in general medical journals </h1> <div class="inline-authors"> <div class="authors"> <div class="authors-list"> <span class="authors-list-item "><a class="full-name" href="/?term=Kulkarni+AV&cauthor_id=19738094" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Abhaya V Kulkarni">Abhaya V Kulkarni</a><sup class="affiliation-links"><span class="author-sup-separator"> </span><a class="affiliation-link" title="Hospital for Sick Children, Room 1503, 555 University Ave, Toronto, ON, Canada M5G 1X8. abhaya.kulkarni@sickkids.ca" href="#full-view-affiliation-1" ref="linksrc=author_aff"> 1 </a></sup><span class="comma">, </span></span><span class="authors-list-item "><a class="full-name" href="/?term=Aziz+B&cauthor_id=19738094" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Brittany Aziz">Brittany Aziz</a><span class="comma">, </span></span><span class="authors-list-item "><a class="full-name" href="/?term=Shams+I&cauthor_id=19738094" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Iffat Shams">Iffat Shams</a><span class="comma">, </span></span><span class="authors-list-item "><a class="full-name" href="/?term=Busse+JW&cauthor_id=19738094" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Jason W Busse">Jason W Busse</a></span> </div> </div> </div> <div class="short-article-details"> Affiliations <button class="more-details" id="toggle-authors" data-alt-text="Collapse" aria-controls="expanded-authors" aria-expanded="false" data-pinger-ignore data-fetch-url="/19738094/long-authors/" data-id-prefix=""> <span class="title"> Expand </span> </button> </div> <div class="extended-article-details" id="expanded-authors" aria-hidden="true"> <div class="expanded-authors" id="full-view-expanded-authors"> <div class="affiliations"> <h3 class="title"> Affiliation </h3> <ul class="item-list"> <li data-affiliation-id="full-view-affiliation-1" id="full-view-affiliation-1" ><sup class="key">1</sup> Hospital for Sick Children, Room 1503, 555 University Ave, Toronto, ON, Canada M5G 1X8. abhaya.kulkarni@sickkids.ca</li> </ul> </div> </div> </div> <ul class="identifiers" id="full-view-identifiers"> <li> <span class="identifier pubmed"> <span class="id-label"> PMID: </span> <strong class="current-id" title="PubMed ID">19738094</strong> </span> </li> <li> <span class="identifier doi"> <span class="id-label"> DOI: </span> <a class="id-link" target="_blank" rel="noopener" ref="linksrc=article_id_link&article_id=10.1001/jama.2009.1307&id_type=DOI" href="https://doi.org/10.1001/jama.2009.1307" data-ga-category="full_text" data-ga-action="DOI" > 10.1001/jama.2009.1307 </a> </span> </li> </ul> <div class="in-clipboard-label " hidden> Item in Clipboard </div> </div> <div class="short-view" id="short-view-heading"> <div class="publication-type" >Comparative Study</div> <h1 class="heading-title"> Comparisons of citations in Web of Science, Scopus, and Google Scholar for articles published in general medical journals </h1> <div class="short-citation"> <span class="authors-list"> <span class="authors-list-item "><span class="full-name">Abhaya V Kulkarni</span><span class="citation-separator"> et al.</span></span> </span> <span class="citation-journal"> JAMA<span class="citation-separator">.</span> </span> <span class="date"> <time class="citation-year" datetime="2009">2009</time><span class="citation-separator">.</span> </span> </div> <div class="more-article-details-section with-display-settings"> <button class="more-article-details" id="toggle-article-details" data-alt-text="Hide details" ref="linksrc=toggle_article_details" aria-controls="full-article-details" aria-expanded="false" data-fetch-url="/19738094/long-authors/" data-id-prefix=""> <span class="title">Show details</span> </button> <div class="display-options" data-format-key="format" data-default-format-value="abstract" data-current-format-value="abstract" role="region"> <button class="trigger usa-button" title="Change format" data-ga-category="display_options" data-ga-action="display_options_dialog"> <span class="button-label">Display options</span> </button> <div class="dropdown" hidden> <div class="title"> Display options </div> <div class="content"> <div class="format-container"> <span class="option-label"> Format </span> <select name="format" data-initial-value="abstract" aria-label="Display format" id="mobile-display-format"> <option value="abstract">Abstract</option> <option value="pubmed">PubMed</option> <option value="pmid">PMID</option> </select> </div> </div> </div> </div> </div> <div class="extended-article-details" id="full-article-details" aria-hidden="true"> <div class="article-citation"> <div class="article-source"> <div class="journal-actions dropdown-block"><button id="short-view-journal-trigger" class="journal-actions-trigger trigger" ref="linksrc=journal_actions_btn" title="JAMA" tabindex="0" aria-controls="short-view-journal" aria-expanded="false" aria-label="Toggle dropdown menu for journal JAMA" data-pinger-ignore> JAMA </button><div id="short-view-journal" class="journal-actions-dropdown dropdown dropdown-container" hidden aria-label="Dropdown menu for journal JAMA"><div class="title">Actions</div><div class="content"><ul class="journal-actions-links"><li><a class="search-in-pubmed-link dropdown-block-link" href="/?term=%22JAMA%22%5Bjour%5D&sort=date&sort_order=desc" data-href="/?term=%22JAMA%22%5Bjour%5D&sort=date&sort_order=desc" ref="linksrc=search_in_pubmed_journal_name_link&journal_abbrev=JAMA" data-ga-category="search" data-ga-action="journal_link" data-ga-label="JAMA"> Search in PubMed </a></li><li><a class="search-in-nlm-catalog-link dropdown-block-link" ref ="linksrc=search_in_nlm_catalog_link" href="https://www.ncbi.nlm.nih.gov/nlmcatalog?term=%22JAMA%22%5BTitle+Abbreviation%5D" data-ga-category="search_catalog" data-ga-action="journal_link" data-ga-label="JAMA"> Search in NLM Catalog </a></li><li><a class="add-to-search-link dropdown-block-link" ref ="linksrc=add_to_search_link" role="button" data-search-term='"JAMA"[jour]' data-ga-category="search" data-ga-action="add_to_search" data-ga-label='"JAMA"[jour]' href="#"> Add to Search </a></li></ul></div></div></div><span class="period">. </span><span class="cit">2009 Sep 9;302(10):1092-6.</span> </div> <span class="citation-doi"> doi: 10.1001/jama.2009.1307. </span> </div> <div class="expanded-authors" id="short-view-expanded-authors"> <div class="authors"> <h3 class="title"> Authors </h3> <div class="authors-list"> <span class="authors-list-item "><a class="full-name" href="/?term=Kulkarni+AV&cauthor_id=19738094" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Abhaya V Kulkarni">Abhaya V Kulkarni</a><sup class="affiliation-links"><span class="author-sup-separator"> </span><a class="affiliation-link" title="Hospital for Sick Children, Room 1503, 555 University Ave, Toronto, ON, Canada M5G 1X8. abhaya.kulkarni@sickkids.ca" href="#short-view-affiliation-1" ref="linksrc=author_aff"> 1 </a></sup><span class="comma">, </span></span><span class="authors-list-item "><a class="full-name" href="/?term=Aziz+B&cauthor_id=19738094" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Brittany Aziz">Brittany Aziz</a><span class="comma">, </span></span><span class="authors-list-item "><a class="full-name" href="/?term=Shams+I&cauthor_id=19738094" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Iffat Shams">Iffat Shams</a><span class="comma">, </span></span><span class="authors-list-item "><a class="full-name" href="/?term=Busse+JW&cauthor_id=19738094" ref="linksrc=author_name_link" data-ga-category="search" data-ga-action="author_link" data-ga-label="Jason W Busse">Jason W Busse</a></span> </div> </div> <div class="affiliations"> <h3 class="title"> Affiliation </h3> <ul class="item-list"> <li data-affiliation-id="short-view-affiliation-1" id="short-view-affiliation-1" ><sup class="key">1</sup> Hospital for Sick Children, Room 1503, 555 University Ave, Toronto, ON, Canada M5G 1X8. abhaya.kulkarni@sickkids.ca</li> </ul> </div> </div> <ul class="identifiers" id="short-view-identifiers"> <li> <span class="identifier pubmed"> <span class="id-label"> PMID: </span> <strong class="current-id" title="PubMed ID">19738094</strong> </span> </li> <li> <span class="identifier doi"> <span class="id-label"> DOI: </span> <a class="id-link" target="_blank" rel="noopener" ref="linksrc=article_id_link&article_id=10.1001/jama.2009.1307&id_type=DOI" href="https://doi.org/10.1001/jama.2009.1307" data-ga-category="full_text" data-ga-action="DOI" > 10.1001/jama.2009.1307 </a> </span> </li> </ul> <div class="in-clipboard-label " hidden> Item in Clipboard </div> </div> </div> </header> <div class="actions-buttons inline"><div class="inner-wrap"><button class="full-text-links-button full-text-links-dialog-trigger" title="Open dialog with full text links" ref="linksrc=full_text_links"> Full text links </button><button class="citation-button citation-dialog-trigger" aria-label="Open dialog with citation text in different styles" data-ga-category="save_share" data-ga-action="cite" data-ga-label="open" data-all-citations-url="/19738094/citations/" data-citation-style="nlm" data-pubmed-format-link="/19738094/export/"><span class="button-label">Cite</span></button><button class="more-actions-button more-actions-dialog-trigger" title="Open dialog with more actions to take" ref="linksrc=more_actions_btn"></button><div class="display-options" data-format-key="format" data-default-format-value="abstract" data-current-format-value="abstract" role="region"><button class="trigger usa-button" title="Change format" data-ga-category="display_options" data-ga-action="display_options_dialog"><span class="button-label">Display options</span></button><div class="dropdown" hidden><div class="title"> Display options </div><div class="content"><div class="format-container"><span class="option-label"> Format </span><select name="format" data-initial-value="abstract" aria-label="Display format" id="inline-actions-display-format"><option value="abstract">Abstract</option><option value="pubmed">PubMed</option><option value="pmid">PMID</option></select></div></div></div></div></div></div> <div class="abstract" id="abstract"> <h2 class="title"> Abstract </h2> <div class="abstract-content selected" id="eng-abstract"> <p> <strong class="sub-title"> Context: </strong> Until recently, Web of Science was the only database available to track citation counts for published articles. Other databases are now available, but their relative performance has not been established. </p> <p> <strong class="sub-title"> Objective: </strong> To compare the citation count profiles of articles published in general medical journals among the citation databases of Web of Science, Scopus, and Google Scholar. </p> <p> <strong class="sub-title"> Design: </strong> Cohort study of 328 articles published in JAMA, Lancet, or the New England Journal of Medicine between October 1, 1999, and March 31, 2000. Total citation counts for each article up to June 2008 were retrieved from Web of Science, Scopus, and Google Scholar. Article characteristics were analyzed in linear regression models to determine interaction with the databases. </p> <p> <strong class="sub-title"> Main outcome measures: </strong> Number of citations received by an article since publication and article characteristics associated with citation in databases. </p> <p> <strong class="sub-title"> Results: </strong> Google Scholar and Scopus retrieved more citations per article with a median of 160 (interquartile range [IQR], 83 to 324) and 149 (IQR, 78 to 289), respectively, than Web of Science (median, 122; IQR, 66 to 241) (P < .001 for both comparisons). Compared with Web of Science, Scopus retrieved more citations from non-English-language sources (median, 10.2% vs 4.1%) and reviews (30.8% vs 18.2%), and fewer citations from articles (57.2% vs 70.5%), editorials (2.1% vs 5.9%), and letters (0.8% vs 2.6%) (all P < .001). On a log(10)-transformed scale, fewer citations were found in Google Scholar to articles with declared industry funding (nonstandardized regression coefficient, -0.09; 95% confidence interval [CI], -0.15 to -0.03), reporting a study of a drug or medical device (-0.05; 95% CI, -0.11 to 0.01), or with group authorship (-0.29; 95% CI, -0.35 to -0.23). In multivariable analysis, group authorship was the only characteristic that differed among the databases; Google Scholar had significantly fewer citations to group-authored articles (-0.30; 95% CI, -0.36 to -0.23) compared with Web of Science. </p> <p> <strong class="sub-title"> Conclusion: </strong> Web of Science, Scopus, and Google Scholar produced quantitatively and qualitatively different citation counts for articles published in 3 general medical journals. </p> </div> </div> <p class="disclaimer" id="disclaimer"> <a href="/disclaimer/" target="_blank" data-ga-category="literature_resources" data-ga-action="disclaimer_link" data-ga-label="under_abstract">PubMed Disclaimer</a> </p> <div class="similar-articles" id="similar"> <h2 class="title"> Similar articles </h2> <ul class="articles-list" id="similar-articles-list"> <li class="full-docsum"> <div class="docsum-content" style="display:inline;"> <a class="docsum-title" href="/31886636/" ref="article_id=31886636&linksrc=similar_articles_link&ordinalpos=1" data-ga-category="similar_article" data-ga-action="31886636" data-ga-label=""> The difference in referencing in Web of Science, Scopus, and Google Scholar. </a> <div class="docsum-citation full-citation"> <span class="docsum-authors full-authors">Anker MS, Hadzibegovic S, Lena A, Haverkamp W.</span> <span class="docsum-authors short-authors">Anker MS, et al.</span> <span class="docsum-journal-citation full-journal-citation">ESC Heart Fail. 2019 Dec;6(6):1291-1312. doi: 10.1002/ehf2.12583. 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Comparisons of citations in Web of Science, Scopus, and Google Scholar for articles published in general medical journals - PubMed