The parent to your comment refers to "determine" in the statistical sense (just as in the submitted article), and so this point needs to be looked at further.
On average, men and women with the same size fingertips perform at the same level so once you know the size of someones fingertips knowing their gender is useless (in this context). What more do you want to study?
"(Finger size does not explain all individual variability, however; there are differences between people with the same size fingers, perhaps as a result of differences in the mechanical properties of skin or in how each person's brain processes the information.)"
"However, other types of tactile tasks may not work the same way, he adds. For example, passively pressing the skin against a textured object--as the study participants did--involves different neuronal pathways than actively moving the fingers around an object and may be controlled differently."
You are correct that the cited study found for its sample "when the scientists looked at the results by finger size, they found that the sex difference disappeared." Then one would want to check other forms of touch perception, as mentioned in the submitted article, try another sample for replication,
