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Electronic culling of the clinical research literature: Filters to reduce the burden of hand searching

Date and Location




Saturday 21 September 2013 - 10:30 - 12:00


Presenting author and contact person

Presenting author

Nancy Wilczynski

Contact person

Nancy Wilczynski
Abstract text
Background: To facilitate the transfer of new, valid, relevant knowledge into clinical practice, research staff in the Health Information Research Unit at McMaster University have created a health knowledge refinery (HKR). The HKR begins with critical appraisal of original and review studies in 122 top clinical journals and leads to the creation of the McMaster PLUS (MacPLUS) database. The time and resources to critically appraise the literature are substantial. Objectives: To determine if Clinical Queries search filters (available for use in PubMed) for large bibliographic databases could be modified to electronically cull the clinical research literature to reduce the burden of hand searching. Methods: The Clinical Queries were modified to include only text words and a NOT string to exclude irrelevant content. A retrospective database of all content indexed in the 122 journals was created by searching Medline via PubMed for a 17 month period. We tested the modified Clinical Queries in this retrospective database to determine if articles contained in the MacPLUS database were retrieved by the modified Clinical Queries. Results: 66,939 articles were downloaded from PubMed for the 122 journals over 17 months of publishing, May 1, 2010 to September 30, 2011. This is the number of articles that HiRU staff would need to review over 17 months (average of 3,938 articles per month – at a time estimate of 92 hours per month). Of these 66,939 articles 3,701 (5.5%) met our criteria for the MacPLUS database. Given prior validation of the search filters, results are shown in the Table using all articles rather than showing the results for the development and validation data sets. Use of the new filters reduced manual processing time by 55%. Conclusions: Search filters can be used to electronically cull the clinical research literature to reduce the burden of hand searching.