Summary description of included studies
| Study | Country | Study setting | Study design | Study period | No of patients (deaths) | Effect estimate: OR (95% CI) | Quality assessment rating |
| Duke11 | Papua New Guinea | 5 hospitals (3 in highland, 1 coastal and 1 inland) | Prospective before-and-after controlled study | 2005–2007 | 11 291 (489) | 0.64 (0.52 to 0.78) | Moderate |
| Gray13 | Lao PDR | 20 district hospitals | Prospective before-and-after controlled study | 2011–2013 | 1403 (25) | 0.32 (0.13 to 0.80) | Moderate |
| Graham14 | Nigeria | 12 secondary level hospitals in Southwest Nigeria (Oyo, Ondo, Ogun, and Osun states) | Stepped-wedge cluster randomised trial with a prospective before-and-after extended analysis | 2015–2017 | 2858 (195) | 0.46 (0.23 to 0.92) | Strong |
| Duke12 | Papua New Guinea | 38 rural hospitals | Prospective before-and-after controlled study | 2015–2017 | 18 933 (530) | 0.47 (0.39 to 0.57) | Moderate |