“…Out of the 21 published articles, 3 were reviews [ 2 , 3 , 4 ] and 18 were original research papers [ 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 ], that can be roughly separated into 6 categories ( Figure 3 ).…”