Methods and references

Contextual citations appear beside each decision in the analysis. Cite the source that supports the specific method you used, rather than citing this interface as methodological authority.

  1. Choosing a model and pooling binary outcomes

    Deeks JJ, Higgins JPT, Altman DG, McKenzie JE, Veroniki AA. Chapter 10: Analysing data and undertaking meta-analyses. Cochrane Handbook, version 6.5 (2024). Sections 10.4.1, 10.4.4.1, 10.5.2 and 10.10.4.

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  2. Odds ratios, log scales and event definitions

    Higgins JPT, Li T, Deeks JJ. Chapter 6: Choosing effect measures and computing estimates of effect. Cochrane Handbook, version 6.5 (2024). Sections 6.1.2, 6.3.1, 6.4 and 6.5.2.3.

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  3. Original Mantel–Haenszel method

    Mantel N, Haenszel W. Statistical aspects of the analysis of data from retrospective studies of disease. J Natl Cancer Inst. 1959;22(4):719–748. doi:10.1093/jnci/22.4.719.

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  4. Estimating between-study variance

    Veroniki AA, et al. Methods to estimate the between-study variance and its uncertainty in meta-analysis. Res Synth Methods. 2016;7(1):55–79. doi:10.1002/jrsm.1164.

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  5. Modified Knapp–Hartung confidence intervals

    Röver C, Knapp G, Friede T. Hartung-Knapp-Sidik-Jonkman approach and its modification for random-effects meta-analysis with few studies. BMC Med Res Methodol. 2015;15:99. doi:10.1186/s12874-015-0091-1.

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  6. The R software used for this analysis

    Viechtbauer W. Conducting meta-analyses in R with the metafor package. J Stat Softw. 2010;36(3):1–48. doi:10.18637/jss.v036.i03.

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  7. Implementation details and interval options

    metafor documentation: rma.uni (REML, DL, test="adhoc" and test="z") and rma.mh. Consult the downloaded session information for the version actually used.

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  8. When funnel plots and asymmetry tests are appropriate

    Page MJ, Higgins JPT, Sterne JAC. Cochrane Handbook v6.5 (2024), Chapter 13, sections 13.3.4.2 and 13.3.4.4: Assessing risk of bias due to missing evidence.

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  9. The 10-study rule and effect-measure restrictions

    Sterne JAC, et al. Recommendations for examining and interpreting funnel plot asymmetry in meta-analyses of randomised controlled trials. BMJ. 2011;343:d4002.

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  10. Original Egger regression test

    Egger M, Davey Smith G, Schneider M, Minder C. Bias in meta-analysis detected by a simple, graphical test. BMJ. 1997;315:629–634.

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  11. Implementation of regression tests for asymmetry

    metafor documentation: regtest. Original Egger implementation: model="lm", predictor="sei"; a weighted regression with multiplicative dispersion.

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  12. Binomial models for single-group proportions

    Lin L, Chu H. Meta-analysis of proportions using generalized linear mixed models. Epidemiology. 2020;31(5):713–717.

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  13. Estimating a mean from a median and quartiles or range

    Luo D, Wan X, Liu J, Tong T. Optimally estimating the sample mean from the sample size, median, mid-range, and/or mid-quartile range. Stat Methods Med Res. 2018;27(6):1785–1805.

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  14. Estimating an SD from a range or interquartile range

    Wan X, Wang W, Liu J, Tong T. Estimating the sample mean and standard deviation from the sample size, median, range and/or interquartile range. BMC Med Res Methodol. 2014;14:135.

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  15. Estimating an SD from the five-number summary

    Shi J, Luo D, Weng H, et al. Optimally estimating the sample standard deviation from the five-number summary. Res Synth Methods. 2020;11(5):641–654.

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  16. Checking medians and quartiles for skewed data

    Shi J, Luo D, Wan X, et al. Detecting the skewness of data from the five-number summary and its application in meta-analysis. Stat Methods Med Res. 2023;32(7):1338–1360.

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  17. Standard error of an AUROC from group sizes

    Hanley JA, McNeil BJ. The meaning and use of the area under a receiver operating characteristic (ROC) curve. Radiology. 1982;143(1):29–36.

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  18. Why funnel plots mislead for proportions

    Hunter JP, Saratzis A, Sutton AJ, Boucher RH, Sayers RD, Bown MJ. In meta-analyses of proportion studies, funnel plots were found to be an inaccurate method of assessing publication bias. J Clin Epidemiol. 2014;67(8):897–903.

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  19. Implementation of logistic meta-analysis

    metafor documentation: rma.glmm. Logit-binomial models for proportions; maximum likelihood with adaptive quadrature. MetaLab uses its t-based interval (k − 1 degrees of freedom) for the random-effects model.

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  20. Joint synthesis of sensitivity and specificity

    Takwoingi Y, et al. Undertaking meta-analysis. Cochrane Handbook for Systematic Reviews of Diagnostic Test Accuracy. 2023. Chapter 10.

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  21. How the bivariate and HSROC diagnostic models relate

    Harbord RM, Deeks JJ, Egger M, Whiting P, Sterne JAC. A unification of models for meta-analysis of diagnostic accuracy studies. Biostatistics. 2007;8(2):239–251.

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  22. What a random-effects average means, and prediction intervals

    Higgins JPT, Thompson SG, Spiegelhalter DJ. A re-evaluation of random-effects meta-analysis. J R Stat Soc Ser A Stat Soc. 2009;172(1):137–159.

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  23. Why to report prediction intervals

    IntHout J, Ioannidis JPA, Rovers MM, Goeman JJ. Plea for routinely presenting prediction intervals in meta-analysis. BMJ Open. 2016;6(7):e010247.

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  24. Judging consistency from the study results

    Guyatt GH, Oxman AD, Kunz R, et al. GRADE guidelines: 7. Rating the quality of evidence: inconsistency. J Clin Epidemiol. 2011;64(12):1294–1302.

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  25. Why I² depends on study size

    Rücker G, Schwarzer G, Carpenter JR, Schumacher M. Undue reliance on I² in assessing heterogeneity may mislead. BMC Med Res Methodol. 2008;8:79.

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  26. Why I² doesn't show how much results vary

    Borenstein M, Higgins JPT, Hedges LV, Rothstein HR. Basics of meta-analysis: I² is not an absolute measure of heterogeneity. Res Synth Methods. 2017;8(1):5–18.

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  27. Bivariate binomial model for diagnostic accuracy

    Chu H, Cole SR. Bivariate meta-analysis of sensitivity and specificity with sparse data: a generalized linear mixed model approach. J Clin Epidemiol. 2006;59(12):1331–1332.

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  28. Why diagnostic accuracy needs a different asymmetry test

    Deeks JJ, Macaskill P, Irwig L. The performance of tests of publication bias and other sample size effects in systematic reviews of diagnostic test accuracy was assessed. J Clin Epidemiol. 2005;58(9):882–893.

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  29. Implementation of the bivariate binomial model

    lme4 documentation: glmer. Binomial models with correlated random effects fitted using the Laplace approximation (nAGQ=1). MetaLab calculates normal (Wald) intervals from the fitted estimates and standard errors, as Cochrane’s MetaDAS macro does.

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  30. Adjusted estimates and non-randomised studies

    Reeves BC, et al. Cochrane Handbook v6.5 (2024), Chapter 24: Including non-randomized studies on intervention effects.

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  31. When AUROC and prediction-model performance can be pooled

    Debray TPA, et al. A guide to systematic review and meta-analysis of prediction model performance. BMJ. 2017;356:i6460. doi:10.1136/bmj.i6460.

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  32. Pooling AUCs from studies of the same diagnostic test

    Zhou XH. Empirical Bayes combination of estimated areas under ROC curves using estimating equations. Med Decis Making. 1996;16(1):24–28. doi:10.1177/0272989X9601600109.

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  33. Fixed-effect and random-effects pooling of ROC curves and their areas

    Hellmich M, Abrams KR, Sutton AJ. Bayesian approaches to meta-analysis of ROC curves. Med Decis Making. 1999;19(3):252–264. doi:10.1177/0272989X9901900304.

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  34. AUROC analysis scale and assumptions

    Snell KIE, Ensor J, Debray TPA, Moons KGM, Riley RD. Meta-analysis of prediction model performance across multiple studies: Which scale helps ensure between-study normality for the C-statistic and calibration measures? Stat Methods Med Res. 2018;27(11):3505–3522. doi:10.1177/0962280217705678.

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