Table 2.
Results of subgroup analysis of included literatures.
| Subgroup | N | SMD (95% CI) | Z | P | Heterogeneity | Model | |
|---|---|---|---|---|---|---|---|
| I 2 (%) | P | ||||||
| Ethnicity | |||||||
| Asians | 9 | 1.42 (1.27, 1.58) | 18.11 | <0.00001 | 98% | <0.00001 | R |
| African | 1 | 1.75 (1.26, 2.24) | 7.01 | <0.00001 | NA | NA | R |
| Sample size | |||||||
| Large | 4 | 1.67 (0.40, 2.95) | 2.57 | 0.01 | 98% | <0.00001 | R |
| Small | 6 | 1.17 (0.96, 1.37) | 11.28 | <0.00001 | 96% | <0.00001 | R |
| Period | |||||||
| Active | 3 | 3.67 (3.23, 4.11) | 16.38 | <0.00001 | 98% | <0.00001 | R |
| Inactive | 3 | 1.86 (1.45, 2.27) | 8.93 | <0.00001 | 97% | <0.00001 | R |
| All | 10 | 3.25 (2.21, 4.29) | 6.13 | <0.00001 | 98% | <0.00001 | R |
N: number; CI: confidence interval; R: random-effect model; SMD: standard mean difference; NA: not available.