APSG Comment: Most eyelid surgery in Korea is performed on young patients. So why in the world would eyelid surgery cause more pain in young Asian men than it does in young Asian women?
Most likely, it doesn't. Or at least doesn't really.
Unnecessarily complex medical pain scales are highly confusing and nearly impossible for most people to understand unless, perhaps, you're an experienced sadomasochist (honestly, who can confidently distinguish level 4 pain from level 3 or 5? And what on earth is a 10 -- having a root canal without anesthesia or being slowly eaten by a shark?).
On top of that, pain ratings are highly subjective person to person, nationality to nationality, and quite probably sex to sex. In other words, the same exact amount of nerve stimulation may be perceived as negligible by groups who tend to be more stoic but horrific among the prima donnas.
Pain is thus a sensation sent by nerve fibers to the brain that then must interpret it. Interpretation is a subjective process influenced by mind-set, or rather a wide range of variables ranging from level of understanding to degree of anxiety to basic personality traits and so on.
One explanation, then, for the difference in pain noted between men and women in this study is not that eyelid surgery actually irritates the nerve endings more in men as a group but rather that Korean women handle this and many of life's other petty inconveniences with more maturity and calm.
Ask any experienced facial surgeon if he or she finds the outcome of this study even the least bit surprising and you're likely to elicit a big laugh.