Additional file 1: Table S1. Search strategy for PubMed. Table S2. Search strategy for Embase. Table S3. Search strategy for Cochrane Library. Table S4. Search strategy for Web of Science. Table S5. Mean and standard deviations of the uUMOD included in the meta-analysis. Fig. S1. Egger plot shows detailing publication bias in the included studies. Fig. S2. Galbraith radial plot of Heterogeneity analysis. Fig. S3. Sensitivity analysis to test the robustness of the pooled Standardized Mean Difference by leave-one-out method. Fig. S4. Sensitivity analysis to test the robustness of the pooled Odds Ratio by leave-one-out method. Fig. S5. Meta-regression plot of the association between SMD of the uUMOD with age. MOOSE checklist