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Cochrane Handbook for Systematic Reviews of Diagnostic Test Accuracy

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Cochrane Handbook for Systematic Reviews of Diagnostic Test Accuracy Cochrane Handbook for Systematic Reviews of Diagnostic Test Accuracy Chapter 10 Analysing and Presenting Results Petra Macaskill, Constantine Gatsonis, Jonathan Deeks, Roger Harbord, Yemisi Takwoingi. Version 1.0 Released December 23rd 2010. ©The Cochrane Collaboration Please cite this version as: Macaskill P, Gatsonis C, Deeks JJ, Harbord RM, Takwoingi Y. Chapter 10: Analysing and Presenting Results. In: Deeks JJ, Bossuyt PM, Gatsonis C (editors), Cochrane Handbook for Systematic Reviews of Diagnostic Test Accuracy Version 1.0. The Cochrane Collaboration, 2010. Available from: http://srdta.cochrane.org/. Saved date and time 23/12/2010 15:08 Jon Deeks 1 | Page Contents 10.1 Introduction ....................................................................................................................................................... 4 10.1.1 Aims of meta-analysis for DTA reviews....................................................................................................... 4 10.1.2 When not to use a meta-analysis in a review ................................................................................................ 5 10.1.3 How does meta-analysis of diagnostic test accuracy differ from meta-analysis of interventions? ................ 5 10.1.4 Questions which can be addressed in DTA analyses .................................................................................... 6 10.1.4.1 What is the accuracy of a test? ............................................................................................................ 6 10.1.4.2 How does the accuracy vary with clinical and methodological characteristics? ................................. 6 10.1.4.3 How does the accuracy of two or more tests compare? ....................................................................... 6 10.1.5 Planning the analysis .................................................................................................................................... 7 10.1.6 Writing the analysis section of the protocol .................................................................................................. 7 10.2 Key concepts ..................................................................................................................................................... 8 10.2.1 Disease status ................................................................................................................................................ 8 10.2.2 Types of test data .......................................................................................................................................... 9 10.2.3 Analysis of a primary test accuracy study ..................................................................................................... 9 10.2.3.1 Sensitivity and Specificity ................................................................................................................. 10 10.2.3.2 Predictive values ............................................................................................................................... 10 10.2.3.3 Likelihood ratios ............................................................................................................................... 10 10.2.3.4 Diagnostic odds ratios ....................................................................................................................... 11 10.2.4 Positivity thresholds .................................................................................................................................... 11 10.2.5 ROC curves ................................................................................................................................................. 13 10.2.6 Relationships between ROC curves, diagnostic odds ratios and Q* ........................................................... 14 10.3 Graphical and tabular presentation .................................................................................................................. 15 10.3.1 Summary ROC plots ................................................................................................................................... 15 10.3.2 Linked ROC plots ....................................................................................................................................... 16 10.3.3 Coupled forest plots .................................................................................................................................... 16 10.3.4 Example 1: Anti-CCP for the diagnosis of rheumatoid arthritis - Descriptive Plots. .................................. 16 10.3.5 Tables of results .......................................................................................................................................... 18 10.4 Meta-analytical summaries .............................................................................................................................. 18 10.4.1 Should I estimate a SROC curve or a summary point? ............................................................................... 18 10.4.2 Meta-analytical methods not routinely used in Cochrane Reviews ............................................................. 19 10.4.3 Heterogeneity .............................................................................................................................................. 20 10.5 Model fitting .................................................................................................................................................... 20 10.5.1 Moses-Littenberg SROC curves (RevMan) ................................................................................................ 20 10.5.1.1 Properties of the curve ...................................................................................................................... 21 10.5.1.2 Choice of weights .............................................................................................................................. 22 10.5.2 Hierarchical models .................................................................................................................................... 22 10.5.2.1 Bivariate model ................................................................................................................................. 24 10.5.2.2 Example 1 continued: Anti-CCP for the diagnosis of rheumatoid arthritis. ..................................... 25 10.5.2.3 The Rutter and Gatsonis HSROC model ........................................................................................... 26 10.5.2.4 Example 2: Rheumatoid Factor as a marker for Rheumatoid Arthritis. ........................................... 28 10.5.3 Investigating heterogeneity ......................................................................................................................... 29 10.5.3.1 Heterogeneity and Regression Analysis using the Bivariate model .................................................. 29 10.5.3.2 Example 1 (cont).: Investigation of heterogeneity in diagnostic performance of anti-CCP ............. 31 10.5.3.3 Heterogeneity and Regression Analysis using the Rutter and Gatsonis HSROC model ................... 32 10.5.3.4 Criteria for model selection ............................................................................................................... 34 10.5.3.5 Example 2 (cont.): Investigating heterogeneity in diagnostic accuracy of Rheumatoid Factor ........ 35 10.5.4 Comparing Index Tests ............................................................................................................................... 36 10.5.4.1 Test comparisons based on all available studies ................................................................................ 36 10.5.4.2 Test comparisons using the Bivariate model ..................................................................................... 36 10.5.4.3 Example 3: CT versus MRI for the diagnosis of coronary artery disease .......................................... 38 10.5.4.4 Test comparisons using the Rutter and Gatsonis HSROC model ...................................................... 39 10.5.4.5 Test comparison based on studies that directly compare tests ........................................................... 40 10.5.4.6 Example 3 (cont.): CT versus MRI for the diagnosis of coronary artery disease .............................. 41 10.5.5 Computer software ...................................................................................................................................... 42 10.5.6 Approaches to analysis with small numbers of studies ............................................................................... 43 10.6 Special topics ................................................................................................................................................... 44 10.6.1 Sensitivity analysis ..................................................................................................................................... 44 10.6.2 Investigating and handling verification bias. .............................................................................................. 46 10.6.3 Investigating and handling publication bias ................................................................................................ 46 10.6.4 Developments in meta-analysis for DTA reviews ...................................................................................... 47 2 | Page Appendix ................................................................................................................................................................................
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