Subgroup analyses for pooled analyses of the proportion of mortality according to study design
| Studies | Participants | Proportion | 95% CI | Heterogeneity | |
| 1 year to <2 years | |||||
| Overall# | 62 | 25 770 | 0.12 | 0.09–0.14 | I2=95% |
| RCT | 16 | 2420 | 0.07 | 0.05–0.09 | I2=75% |
| Prospective study | 18 | 769 | 0.11 | 0.05–0.18 | I2=81% |
| Retrospective study | 28 | 22 581 | 0.16 | 0.13–0.19 | I2=95% |
| Test for heterogeneity between subgroups 0.36 | |||||
| 2 to <5 years | |||||
| Overall | 35 | 20 787 | 0.38 | 0.34–0.42 | I2=94% |
| Prospective study | 18 | 1650 | 0.33 | 0.25–0.43 | I2=92% |
| Retrospective study | 17 | 19 092 | 0.43 | 0.38–0.47 | I2=93% |
| Test for heterogeneity between subgroups=0.08 | |||||
| ≥5 years | |||||
| Overall | 32 | 6369 | 0.69 | 0.59–0.78 | I2=98% |
| Prospective study | 9 | 1060 | 0.58 | 0.38–0.78 | I2=97% |
| Retrospective study | 23 | 5309 | 0.73 | 0.61–0.83 | I2=98% |
| Test for heterogeneity between subgroups=0.21 |
Data are presented as n, unless otherwise stated. RCT: randomised controlled trial. #: included data from RCTs.