Summary of articles included in the review by regions
| Region | Countries | References | Study design |
| West Africa | Nigeria=15 | 15 22 23 25 29 30 35 44 54 62 65 72 75 80 84 | 11 SA, 3 cross-sectional, 1 mixed methods |
| Ghana=5 | 27 40 41 90 94 | 3 SA, 2 cross-sectional | |
| Benin=2 | 71 77 | SA | |
| Niger=1 | 97 | Cross-sectional | |
| Cameroon=1 | 69 | SA | |
| Burkina Faso=2 | 42 43 | Cross-sectional | |
| DRC=1 | 13 | ||
| South Africa | South Africa=2 | 34 98 | 1 SA, 1 mixed methods |
| East Africa | |||
| Rwanda=2 | 52 81 | 1 SA, 1 cross-sectional | |
| Malawi=1 | 95 | Natural experiment | |
| Kenya=5 | 9 70 79 82 92 | 3 SDA, 2 cross-sectional | |
| Tanzania=4 | 53 89 96 100 | 2 SDA, 2 cross-sectional | |
| Zambia=2 | 74 93 | 2 SDA | |
| Zimbabwe=1 | 78 | 1 SDA | |
| Ethiopia=24 | 24 32 46–48 50 51 55 56 58–60 63 64 66 68 77 83 85–88 91 99 | 6 SDA, 18 cross-sectional | |
| Multicountry | n=6 | 49 57 61 67 73 76 | 6 SDA |
DRC, Democratic Republic of the Congo; SA, Secondary Data Analysis.