Sample distribution by country
| Survey countries | Survey year | Weighted sample | Percentage |
| Central Africa | |||
| Angola | 2016 | 907 | 9.56 |
| Cameroon | 2018 | 523 | 5.51 |
| Chad | 2015 | 818 | 8.62 |
| West Africa | |||
| Benin | 2018 | 440 | 4.64 |
| Guinea | 2018 | 441 | 4.65 |
| Mali | 2018 | 507 | 5.35 |
| Nigeria | 2018 | 1043 | 10.99 |
| Sierra Leone | 2019 | 586 | 6.18 |
| East Africa | |||
| Burundi | 2017 | 212 | 2.23 |
| Ethiopia | 2016 | 288 | 3.04 |
| Rwanda | 2015 | 150 | 1.59 |
| Tanzania | 2016 | 533 | 5.62 |
| Uganda | 2016 | 729 | 7.69 |
| Southern Africa | |||
| Malawi | 2016 | 1109 | 11.68 |
| South Africa | 2016 | 176 | 1.86 |
| Zambia | 2018 | 664 | 7.00 |
| Zimbabwe | 2015 | 361 | 3.80 |
Source: Demographic and Health Surveys.