ABSTRACT
THE OBJECTIVE: Of the work was to describe the basics of a meta-analysis with features for evaluating models with fixed and random effects, to present principles for interpreting the graphical results of a meta-analysis (forest plot or blobogram) of comparative reviews of randomized clinical trials (RCTs). MATERIAL AND METHODS: To illustrate the possibility of efficient use of the R software environment for meta-analysis, we used the results of RCTs of various tonsillectomy methods already published in the Cochrane Database review. RESULTS: The article provides explanations for the calculation of effect size, heterogeneity statistic, and other meta-analysis statistics and their interpretation for evaluating RCTs and recommendations for choosing a model depending on the on the general research concept. CONCLUSION: The described method allows meta-analysis and gives an idea of the principles for preparing the results of clinical trials with the expectation of their subsequent use in systematic reviews and meta-analysis.
