“…The forty-two studies [ 1 – 3 , 5 , 6 , 8 – 10 , 18 , 19 , 27 , 29 , 34 , 43 , 44 , 52 – 78 ], two studies [ 79 , 80 ] and one study [ 35 ] were conducted using cross-sectional, retrospective cohort and case-control studies respectively. Regarding geographical region, fourteen studies were conducted in Oromia [ 2 , 3 , 9 , 18 , 27 , 44 , 52 , 57 , 59 , 64 , 69 , 76 , 77 , 79 ], eleven studies in Amhara [ 1 , 6 , 19 , 56 , 61 , 66 – 68 , 73 , 75 , 78 ], ten studies in Southern nations nationalities [ 5 , 10 , 34 , 35 , 43 , 53 , 55 , 60 , 62 , 72 ], two studies in Addis Ababa [ 8 , 44 ], two studies in Tigray [ 58 , 80 ], one study in Oromia and Southern nations nationalities [ 54 ], one study in Harari and Dire Dawa [ 63 ] and one study was conducted in each Benishangul Gumuz [ 71 ], Somali [ 74 ], Harari [ 29 ], and Sidama region [ 65 ]. The total sample size of ...…”