Table 3. Subgroup analyses based on regimen characteristics from randomised controlled trials: Comparison 1—Magnesium sulphate versus placebo or no treatment.
| Outcome or subgroup | Studies | Participants | Method (I2) | RR (95% CI) | χ2, P value, I2 |
|---|---|---|---|---|---|
| Subgroups based on LD | |||||
| 1.1 Perinatal death | |||||
| 1.1.4 4-g IV LD | 5 | 2,259 | R (42%) | 0.96 (0.62, 1.49) | 0.57, 0.75, 0% |
| 1.1.5 6-g IV LD | 1 | 2,136 | R (NA) | 1.12 (0.85, 1.47) | |
| 1.1.6 4-g IV and 10-g IM LD | 2 | 9,259 | R (0%) | 1.01 (0.91, 1.12) | |
| 1.2 Stillbirth | |||||
| 1.2.4 4-g IV LD | 6 | 2,961 | F (0%) | 1.25 (0.85, 1.84) | 1.57, 0.21, 36.1% |
| 1.2.5 6-g IV LD | 1 | 120 | F (NA) | No events | |
| 1.2.6 4-g IV and 10-g IM LD | 2 | 9,259 | F (0%) | 0.96 (0.84, 1.10) | |
| 1.3 Neonatal death | |||||
| 1.3.4 4-g IV LD | 6 | 2,294 | R (7%) | 0.86 (0.64, 1.16) | 0.44, 0.80, 0% |
| 1.3.5 6-g IV LD | 3 | 1,434 | R (2%) | 0.83 (0.48, 1.44) | |
| 1.3.6 4-g IV and 10-g IM LD | 2 | 9,259 | R (35%) | 1.03 (0.64, 1.65) | |
| 1.4 Death > 28 days, before discharge | |||||
| 1.4.4 4-g IV LD | 3 | 1,514 | F (0%) | 0.81 (0.43, 1.53) | 0.81, 0.67, 0% |
| 1.4.5 6-g IV LD | 1 | 153 | F (NA) | 2.47 (0.10, 59.70) | |
| 1.4.6 4-g IV and 10-g IM LD | 1 | 9,024 | F (NA) | 1.13 (0.55, 2.31) | |
| Subgroups based on MD | |||||
| 1.1 Perinatal death | |||||
| 1.1.7 LD only | 2 | 747 | R (0%) | 0.92 (0.59, 1.44) | 2.73, 0.44, 0% |
| 1.1.8 1-g/hour IV MD | 1 | 1,255 | R (NA) | 0.81 (0.60, 1.09) | |
| 1.1.9 2–5-g/hour IV MD | 3 | 2,393 | R (71%) | 2.27 (0.35, 14.55) | |
| 1.1.10 5-g/4-hour IM MD | 2 | 9,259 | R (0%) | 1.01 (0.91, 1.12) | |
| 1.2 Stillbirth | |||||
| 1.2.7 LD only | 2 | 747 | F (0%) | 0.96 (0.22, 4.17) | 2.50, 0.48, 0% |
| 1.2.8 1-g/hour IV MD | 2 | 1,957 | F (9%) | 1.22 (0.81, 1.83) | |
| 1.2.9 2–5-g/hour IV MD | 3 | 377 | F (0%) | 5.70 (0.28, 116.87) | |
| 1.2.10 5-g/4-hour IM MD | 2 | 9,259 | F (0%) | 0.96 (0.84, 1.10) | |
| 1.3 Neonatal death | |||||
| 1.3.7 LD only | 2 | 747 | R (0%) | 0.93 (0.58, 1.47) | 0.72, 0.87, 0% |
| 1.3.8 1-g/hour IV MD | 1 | 1,255 | R (NA) | 0.81 (0.59, 1.11) | |
| 1.3.9 2–5-g/hour IV MD | 6 | 1,726 | R (41%) | 0.84 (0.30, 2.33) | |
| 1.3.10 5-g/4-hour IM MD | 2 | 9,259 | R (35%) | 1.03 (0.64, 1.65) | |
| 1.4 Death > 28 days, before discharge | |||||
| 1.4.7 1-g/hour IV MD | 1 | 1,255 | F (NA) | 0.88 (0.44, 1.74) | 0.37, 0.83, 0% |
| 1.4.8 2–5-g/hour IV MD | 3 | 412 | F (0%) | 0.76 (0.19, 3.09) | |
| 1.4.9 5-g/4-hour IM MD | 1 | 9,024 | F (NA) | 1.13 (0.55, 2.31) | |
Test for heterogeneity represented by I2 statistic; where I2 > 30%, summary estimates were calculated using random-effects meta-analysis. Result of test subgroup differences represented by χ2 statistic, P value, and I2 statistic.
CI, confidence interval; F, fixed-effects; g, gram; IM, intramuscular; IV, intravenous; LD, loading dose; MD, maintenance dose; NA, not applicable; R, random-effects; RR, risk ratio.