QUADAS-2 Group. QUADAS-2: a revised tool for the quality assessment of diagnostic accuracy studies

University of Bristol, United Kingdom.
Annals of internal medicine (Impact Factor: 17.81). 10/2011; 155(8):529-36. DOI: 10.1059/0003-4819-155-8-201110180-00009
Source: PubMed


In 2003, the QUADAS tool for systematic reviews of diagnostic accuracy studies was developed. Experience, anecdotal reports, and feedback suggested areas for improvement; therefore, QUADAS-2 was developed. This tool comprises 4 domains: patient selection, index test, reference standard, and flow and timing. Each domain is assessed in terms of risk of bias, and the first 3 domains are also assessed in terms of concerns regarding applicability. Signalling questions are included to help judge risk of bias. The QUADAS-2 tool is applied in 4 phases: summarize the review question, tailor the tool and produce review-specific guidance, construct a flow diagram for the primary study, and judge bias and applicability. This tool will allow for more transparent rating of bias and applicability of primary diagnostic accuracy studies.

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Available from: Marie Westwood, May 13, 2014
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    • "To assess the methodological quality of the included papers, the two reviewers (JHL, LDB) used an adapted version of the QUADAS-2 tool [16]. The adapted version of this tool can be found in eSupplement 1. Extracted data include: characteristics of the study (first author, year, country, condition studied, number of included patients), methods used (pre-processing, dimension reduction, feature selection, classification algorithm), performance measure(s), and validation method. "
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