“…Thirty-four studies were retrospective cohort studies, 2,4,14-45 three were prospective cohort studies, [46][47][48] two were randomized-controlled trials, 49,50 two were propensity matched studies (retrospective 51 and prospective 52 ), one was a retrospective matched-pair analysis, 53 and one was a case-control study. 54 performed in Japan (n = 14), 15,21,24,25,30,31,33,34,39,42,43,45,48,54 USA (n = 6), 14,17,26,35,47,51 Italy (n = 5), 20,22,27,46,52 China (n = 5), 4,32,36,38,44 Germany (n = 3), 23,40,53 Korea (n = 2), 29,36 Finland (n = 2), 37,49 France (n = 1), 28 Taiwan (n = 1), 16 Sweden (n = 1), …”