| Authors | staff | % |
| Macombou P. Congo 2002 [6] | 345 | 4.7% |
| Touré M. Mali 2006 [7] | 105 | 2.1% |
| Hannah M E. Hannha W J. Canada 2000 [8] | - | 3% |
| Our Mali 2018 study | 120 | 3.14% |