Table 1.
Countries included in reviewed studies
| Countries | Number of studies |
| Ethiopia | 20 |
| Nigeria | 12 |
| Ghana | 6 |
| South Africa | 6 |
| Uganda | 2 |
| Kenya | 2 |
| Zimbabwe | 2 |
| Democratic Republic of the Congo | 2 |
| Somalia | 2 |
| Mozambique | 1 |
| Zambia | 1 |
| Togo | 1 |
| Cameroon | 1 |
| Multiple country studies* | 14 |
| Total | 72 |
*Additional sub-Saharan Africa countries included in multiple-country studies were Angola, Benin, Burkina Faso, Cape Verde, Côte d’Ivoire, Gambia, Guinea, Guinea-Bissau, Lesotho, Malawi, Mali, Rwanda, São Tomé and Principe, Senegal, Sierra Leone, Sudan and Tanzania.