Visualization of the results of a meta-analysis of clinical studies

The presented method makes it possible to create a meta-analysis diagram (forest plot, or blobbogram), calculate the basic meta-analysis statistics and interpret them correctly. The article describes an example of construction of a forest plot and creation of its elements in detail, explaining the calculation of the basic meta-analysis statistics: effect size, effect heterogeneity index. The authors provide a description of the underlying features of the meta-analysis of models with fixed and random effects, suggesting recommendations on the choice of model depending on the general concept of the study. Using the example of published data of randomized controlled trials of one of tonsillectomy methods – coblation, the authors built a meta-analysis diagram with the calculation of the main indicators evaluating the effect of clinical impact and its variability. To solve the statistical problems, the authors used R-language software environment, which is currently considered the most powerful and flexible tool for performing statistical analysis of medical data and visualizing its results. The description of the tasks is accompanied with the introduction of full R-language program code, which can be used for reproduction of the results of this study and solution of similar problems on other source data. The article uses terms and concepts related to the meta-analysis method both in English and in Russian.