Objectives: To establish the test sensitivity and specificity of the I2 point estimate for testing selection bias risk in meta-analyses under condition of large versus small trial sample size and large versus small trial number in meta-analysis and to test the null-hypothesis that the differences are not statistically significant.
Methods: Simulation trials will be generated in MS Excel, each consisting of three components, entered in form of three parallel columns: a sequence of subject ID (accession) numbers representing trial subjects; a random sequence of allocation to group A or B and a random sequence of a simulated baseline variable (‘age’) per subject, ranging between 50 to 55. These simulation trials will be included into five types of meta-analyses with large/small numbers of trials, as well as trials with large and small sample sizes. All meta-analyses will be tested using the I2 point estimate. The numbers of true positive, false positive, false negative and true negative test results will be established. From these, the test sensitivity and specificity will be computed for each of the meta-analysis types and statistically compared.
Ethics and dissemination: Ethical approval is not required for simulation-based studies. The results will be disseminated as a prior preprint version and subsequent peer-reviewed publication.