“…Exposure to critical incidents [ 5 , 19 , 22 , 24 , 35 , 37 , 39 , 40 , 41 , 52 , 53 , 64 , 67 , 71 , 78 , 82 , 89 , 90 , 92 , 103 , 104 ] was the most frequently cited negative operational factor, included in 21 studies. High workload [ 8 , 19 , 29 , 31 , 32 , 33 , 36 , 45 , 46 , 47 , 57 , 59 , 66 , 70 , 73 , 74 , 80 , 96 , 98 ] was the second most frequently cited negative operational factor ( n = 20). Thirteen articles identified threats or risk of violence [ 41 , 44 , 45 , 50 , 66 , 69 , 70 , 76 , 77 , 81 , ...…”