“…Among these studies, 6 studies were conducted in China, [23,26,28–30,32] 1 in Japan, [31] 1 in Sweden, [24] 1 in Australia, [25] and 1 in Brazil. [27] Of all the selected studies, 3 presented HRs, [25,26,28] whereas in the other 7 studies, [23,24,27,29–32] HRs were absent, and we needed to calculate the HR s from the survival curves. One study [25] did not give accurate data for follow-up.…”