Fig. 2

Forest plot representing Fisher’s z values concerning the relationship between pIL-6 level and grip strength in male, female and mixed subgroups. Squares show the Fisher’s z values with the grey area reflecting the weight assigned to the study. Horizontal bars indicate 95% confidence intervals (95% CI). The diamond shows the overall effect size (ES) with its corresponding 95% CI. In the case of two studies [24, 25], the coefficients for male and female groups were indicated by m and f, respectively