Evidence Based Library and Information Practice (Sep 2012)
Applying the Narrow Forms of PubMed Methods-based and Topic-based Filters Increases Nephrologists’ Search Efficiency. A Review of: Shariff, S. Z., Sontrop, J. M., Haynes, R. B., Iansavichus, A. V., McKibbon, K. A., Wilczynski, N. L., Weir, M. A., Speechley, M. R., Thind, A. … Garg, A. X. (2012). Impact of PubMed search filters on the retrieval of evidence by physicians. CMAJ: Canadian Medical Association Journal, 184(3), E184-E190. doi: 10.1503/cmaj.101661
Abstract
Objective – To determine whether the use ofPubMed methods-based filters and topic-basedfilters, alone or in combination, improvesphysician searching.Design – Mixed methods, surveyquestionnaire, comparative.Setting – Canada.Subjects – Random sample of Canadiannephrologists (n=153), responses (n=115),excluded (n=15), total (n=100).Methods – The methods are described in detailin a previously published study protocol by asubset of the authors (Shariff et al., 2010).One hundred systematic reviews on renaltherapy were identified using theEvidenceUpdates service(http://plus.mcmaster.ca/EvidenceUpdates)and a clinical question was derived from eachreview. Randomly-selected Canadiannephrologists were randomly assigned aunique clinical question derived from thereviews and asked, by survey, to provide thesearch query they would use to searchPubMed. The survey was administered untilone valid search query for each of the onehundred questions was received. The physician search was re-executed and compared to searches where either or both methods-based and topic-based filters were applied. Nine searches for each question were conducted: the original physician search, a broad and narrow form of the clinical queries therapy filter, a broad and narrow form of the nephrology topic filter and combinations of broad and narrow forms of both filters.Significance tests of comprehensiveness (proportion of relevant articles found) and efficiency (ratio of relevant to non-relevant articles) of the filtered and unfiltered searches were conducted. The primary studies included in the systematic reviews were set as the reference standard for relevant articles.As physicians indicated they did not scan beyond two pages of default PubMed results, primary analysis was also repeated on search results restricted to the first 40 records.The ability of the filters to retrieve highly-relevant or highly-cited articles was also tested, with an article being considered highly-relevant if referenced by UpToDate and highly-cited if its citation count was greater than the median citation count of all relevant articles for that question – there was an average of eight highly-cited articles per question.To reduce the risk of type I error, the conservative method of Bonferroni was applied so that tests with a pMain Results – Response rate 75%. Physician-provided search terms retrieved 46% of relevant articles and a ratio of relevant to non-relevant articles of 1:16 (pConclusion – The use of PubMed search filters improves the efficiency of physician searches and saves time and frustration. Applying clinical filters for quick clinical searches can significantly improve the efficiency of physician searching. Improved search performance has the potential to enhance the transfer of research into practice and improve patient care.
