TABLE 2.
Re-analysis stratified by altitude, age and duration of high-altitude climatic therapy
| Subjects | Sets of results | SMD (95% CI) | Heterogeneity | ||
| I2 | p-value# | ||||
| Overall | 907 | 28 | 0.53 (0.43–0.62) | 85 | <0.001 |
| Altitude MASL | |||||
| ≤2000 | 717 | 22 | 0.53 (0.42–0.64) | 85 | <0.001 |
| >2000 | 190 | 6 | 0.53 (0.32–0.74) | 88 | 0.02 |
| Age group | |||||
| Children | 371 | 14 | 0.24 (0.09–0.38) | 4 | 0.41 |
| Adults | 536 | 14 | 0.75 (0.63–0.88) | 90 | <0.001 |
| Treatment duration weeks | |||||
| ≤4 | 437 | 16 | 0.42 (0.28–0.55) | 74 | <0.001 |
| >4 | 470 | 12 | 0.63 (0.50–0.77) | 90 | <0.001 |
Data are presented as n or %, unless otherwise stated. SMD: standardised mean difference; MASL: metres above sea level. #: p-value is for heterogeneity Chi-squared.