“…Thirty-five studies (92%) were published after 2000 [ 9 , 34 , 35 , 37 , 38 , 40 – 48 , 50 , 51 , 53 – 62 , 64 – 73 ]. Twelve studies (32%) were from the United States of America [ 35 , 36 , 38 , 45 , 50 , 56 , 60 , 62 , 66 , 68 , 70 , 71 ], six studies (16%) were from Germany [ 43 , 47 , 57 , 58 , 67 , 72 , 73 ], five studies (13%) were from China [ 42 , 44 , 51 , 55 , 64 ], three studies were from Sweden [ 34 , 59 , 69 ], two studies were from each Ireland [ 48 , 54 ], Canada [ 40 , 53 ], Scotland [ 46 , 63 ], and South Korea [ 41 , 61 ]. Thus, 13 studies (34%) reported data from non-universal healthcare system [ 35 – 38 , 45 , 50 , 56 , 60 , 62 , 66 , 68 , 70 , 71 ], 12 studies (32%) reported data from universal government-funded healthcare system [ 9 , 34 , 39 , 40 , …”