Summary of findings 7.
Mid‐dose mifepristone (25 mg‐50 mg) versus low‐dose mifepristone (< 25 mg) for emergency contraception
| Mid‐dose mifepristone (25 mg‐50 mg) versus low‐dose mifepristone (< 25 mg) for emergency contraception | ||||||
| Patient or population: women seeking emergency contraception Setting: China (25); family planning clinics Intervention: mifepristone, mid‐dose (25 mg‐50 mg) Comparison: mifepristone, low‐doses (< 25 mg) | ||||||
| Outcomes | Anticipated absolute effects* (95% CI) | Relative effect (95% CI) | № of participants (studies) | Quality of the evidence (GRADE) | Comments | |
| Risk with low‐dose mifepristone (< 25 mg) | Risk with mid‐dose mifepristone (25 mg‐50 mg) | |||||
| Observed number of pregnancies (all women) | 17 per 1000 | 12 per 1000 (9 to 16) | RR 0.73 (0.55 to 0.97) | 11914 (25 RCTs) | ⊕⊕⊕⊕ High | |
| Any side effect | 88 per 1000 | 115 per 1000 (89 to 149) | RR 1.31 (1.01 to 1.70) | 2464 (11 RCTs) | ⊕⊕⊕⊝ Moderate1 | |
| Specific side effects ‐ nausea | 104 per 1000 | 114 per 1000 (100 to 128) | RR 1.10 (0.97 to 1.24) | 7948 (13 RCTs) | ⊕⊕⊕⊝ Moderate2 | |
| Specific side effects ‐ vomiting | 6 per 1000 | 7 per 1000 (4 to 13) | RR 1.22 (0.68 to 2.17) | 6082 (6 RCTs) | ⊕⊕⊕⊝ Moderate2 | |
| Specific side effects ‐ spotting/bleeding after treatment | 69 per 1000 | 127 per 1000 (107 to 151) | RR 1.85 (1.55 to 2.20) | 5078 (11 RCTs) | ⊕⊕⊕⊕ High | |
| Menses ‐ early | 118 per 1000 | 129 per 1000 (103 to 160) | RR 1.09 (0.87 to 1.36) | 2136 (7 RCTs) | ⊕⊕⊝⊝ Low1,2 | |
| Menses ‐ delay | 117 per 1000 | 150 per 1000 (130 to 172) | RR 1.28 (1.11 to 1.47) | 11282 (21 RCTs) | ⊕⊕⊕⊝ Moderate3 | |
| *The risk in the intervention group (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). CI: confidence interval; RR: risk ratio | ||||||
| GRADE Working Group grades of evidence High quality: we are very confident that the true effect lies close to that of the estimate of the effect Moderate quality: we are moderately confident in the effect estimate: the true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different Low quality: our confidence in the effect estimate is limited: the true effect may be substantially different from the estimate of the effect Very low quality: we have very little confidence in the effect estimate: the true effect is likely to be substantially different from the estimate of effect | ||||||
1We downgraded the quality of evidence by one level for risk of bias because we judged allocation concealment to be inadequate in the meta‐analysis. 2We downgraded the quality of evidence by one level for imprecision because the 95% CI overlaps no effect and CI fails to exclude important benefit or important harm. 3We downgraded the quality of evidence by one level for inconsistency because of high heterogeneity in the meta‐analysis.