Table 1 Quality assessment of included case-control studies
| Â | Mahomed et al. | Anorlu et al. | Kiondo et al. | Guerrier et al. | Endeshaw et al. | Grum et al. | Kahsay et al. | Mrema et al. |
|---|---|---|---|---|---|---|---|---|
Selection | ||||||||
 Is the case definition adequate? | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
 Representativeness of cases | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 |
 Selection of Controls | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
 Definition of Controls | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
Comparability | ||||||||
 Comparability of cases and controls based on the design or analysis | 2 | 2 | 1 | 2 | 2 | 2 | 2 | 2 |
Exposure | ||||||||
 Ascertainment of exposure | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
 Same method of ascertainment for cases and controls | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
 Non-Response rate | 0 | 1 | 1 | 0 | 1 | 1 | 1 | 0 |
Total | 7 | 8 | 7 | 7 | 8 | 8 | 7 | 7 |