“… 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 10 studies were conducted in European countries. 6 , 7 , 8 , 15 , 16 , 17 , 18 , 19 , 22 , 25 whereas 25 studies were conducted in Asian countries 9 , 10 , 11 , 20 , 21 , 23 , 24 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 (22 in Japan). 9 , 10 , 11 , 20 , 21 ,…”