2.3. Data analysis procedure
Data were independently extracted and verified by two authors (B.J.M.C and D.L.S), data verification was performed three times. Data extracted from all articles that met the inclusion criteria were included in the calculation of the global prevalence of FLA in swimming pools and recreational waters. To calculate the prevalence of each FLA genera, only data extracted from articles that included molecular methods for the identification of FLA were used. Data analysis was performed by two authors (D.A and B.J.M.C) using Stata software (version 14; Stata Corp, College Station, TX, USA) and GraphPad prism 8.02. A random-effects model meta-analysis was performed to estimate the combined and weighted prevalence of FLA in swimming pools and recreational waters, using a 95% confidence interval, and the results are visualized using a forest plot. Cochrane’s Q test (chi-square) and the HigginsI 2 statistic were used to calculate the heterogeneity index among the selected studies.I 2 values <25%, 25%–50% and >50% meant low, moderate and high heterogeneity, respectively. The Egger’s test was used to assess the significance of publication bias among the selected studies, p < 0.001 was considered significant.