3.
Quality of evidence by contraceptive method
| Study | Comparison groups | Mean difference (95% CI)* | Quality of evidence** |
|---|---|---|---|
| Progestin-only pills | |||
| Ball 1991 | OC NET 350 μg vs LNG 30 μg | --- | High |
| DMPA | |||
| WHO 1983 | DMPA vs NET-EN (60 days) | --- | High |
| NET-EN: 60 days vs 84 days | --- | ||
| Salem 1988 | DMPA vs NET-EN | --- | High |
| Bonny 2009 | DMPA + placebo vs DMPA + E2C | --- | Moderate |
| DMPA + placebo vs no hormonal | 11.00 (2.64 to 19.36); −4.00 (−6.93 to −1.07)a | ||
| Westhoff 2007 | DMPA-IM 150 vs DMPA-SC 104 | --- | Moderate |
| Castle 1978 | DMPA 150 vs DMPA 450 | --- | Low |
| Pantoja 2010 | DMPA vs non-hormonal IUD | 3.17 (2.51 to 3.83)b | Low |
| Tankeyoon 1976 | DMPA vs COC | --- | Low |
| Taneepanichskul 1998 | DMPA vs non-hormonal IUD | --- | Very low |
| Tuchman 2005 | DMPA vs MPA/E2C | --- | Very low |
| DMPA vs COC | --- | ||
| Espey 2000 | DMPA: interval vs postpartum | --- | Very low |
| Norplant | |||
| Sivin 1998 | Norplant vs 2-rod LNG | --- | High |
| Salem 1984 | Norplant vs non-hormonal IUD | 0.47 (0.29 to 0.65)b | Moderate |
| Norplant vs other non- hormonal | 0.74 (0.52 to 0.96)b | ||
| Moore 1995 | Norplant vs DMPA | --- | Low |
| Sule 2005 | Norplant vs non-hormonal IUD | 1.10 (0.36 to 1.84)b | Very low |
| Norplant vs COC | --- | ||
| Levonorgestrel-releasing IUS | |||
| Dal’Ava 2012 | LNG-IUS vs non-hormonal IUD | 2.5% vs −1.3%; −1.4% vs 1.0%a | Moderate |
*
Data shown if groups differed significantly.
**
Grades initially based on study design (RCT = high; prospective non-randomized = moderate; retrospective = low). Downgraded if losses >=25% or if cases were inappropriately excluded.
a
Total body fat (%) and lean body mass (%), respectively.
b
Weight (kg), except Salem 1988, which did not report units (lbs or kg).