The approaches of rating the quality of evidence of systematic reviews of diagnostic accuracy tests are different from systematic reviews of interventional studies. This article systematically introduces the application of GRADE in systematic reviews of diagnostic accuracy tests by a case interpretation and analysis. In this article we present rating workflow in systematic reviews of diagnostic accuracy tests and introduce how to use the GDT website to display the rating results, and interpret the conclusion of systematic reviews based on GRADE results.
Depending on different designs of original studies, systematic reviews of diagnostic studies could be categorized into two kinds:one is based on diagnostic randomized controlled trials, of which the GRADE rating approach is similar to that of interventional systematic reviews; and the other is based on diagnostic accuracy tests, of which the GRADE rating approach is introduced in this article. This article explains the application of GRADE in systematic reviews of diagnostic accuracy tests mainly from the angle of theoretical analysis, including rationales, methods, and challenges.
Comparative diagnostic test accuracy study, a type of diagnostic accuracy test, aims to compare accuracy of two or more index tests in a study. The application of GRADE in comparative test accuracy differs from single test accuracy, mainly including the selection of appropriate comparative study designs, additional criteria for judging risk of bias, and the consequences of using comparative measures of test accuracy. The study focuses on basic principles and methods of GRADE approach in systematic reviews of comparative test accuracy to promote the understanding and application of the method by domestic scholars.