“…With a total of 39 included studies, for the 27 studies that had an N > 1, [24–50] the following data were collected: the total number of subjects included in the studies was 41,178 with an average ratio of 1.525:1 regarding the sex of the sample; 12 studies did not indicate the sex of their sample [25,27,31,34,35,37,38,45,47–50] ; one study by Yusuf et al [32] only indicates the sex of the sample that did present the anatomical variant and consisted of 10 men and 17 women, respectively; and, finally, 14 studies [24,26,28–30,33,39–44,46] show that the cumulative data for males was 2964/5393, which is equivalent to 54.9%, and cumulative data for females was 2429/5393, which is equivalent to 45.1%. Finally, regarding the geographical distribution of the included studies, [24–50,53–64] in 13 studies, the sample was European, which is equivalent to 33.3% of the included studies; in 12 studies, the sample was from North America, which is equivalent to 30.8% of the included studies; and, finally, 14 studies had a sample from Asia, which is equivalent to 35.9% of the studies included in this review (Table 2).…”