Table 1 Ottawa rating for included studies: (* OR ** means criteria fulfilled/maximum score = 9)

Adewale et al.

****

**

**

8

Ahenkorah et al.

****

**

***

9

Ajanga et al.

****

**

***

9

Alem et al.

***

**

***

8

Anchang-Kimbi et al.

****

**

**

8

Ayoya et al.

****

**

**

8

Bolka et al.

****

**

**

8

Coulibaly et al.

****

**

***

9

Derso et al.

****

**

***

9

Egwunyenga et al.

****

**

**

8

Eyo et al.

****

**

**

8

Fairley et al.

****

**

***

9

Feleke et al.

****

**

**

8

Fuseini et al.

****

**

**

8

Gadoth et al.

****

**

***

9

Gedefaw et al.

****

**

**

8

Kawai et al.

***

**

***

8

Kefiyalew et al.

***

**

**

7

Khalid et al.

***

**

***

8

Kihara et al.

****

**

***

9

Mombo-Ngoma et al.

****

**

**

8

Muhangi et al.

****

**

***

9

Murenjekwa et al.

****

**

**

8

Ndyomugyenyi et al.

****

**

**

8

Ouédraogo et al.

****

**

***

9

Oyeyemi et al.

****

**

***

9

Salawu et al.

****

**

**

8

Siegrist et al.

****

**

**

8

Tay et al.

****

**

***

9

Thigpen et al.

****

**

**

8

Tonga et al.

***

**

***

8

Wepnje et al.

****

**

**

8