> Third, we used self-reported data to identify physician sex, which requires respondents to categorize themselves as either male or female; therefore, we could not capture respondents who were transgender. It is possible that transgender physicians chose to either leave this question blank or select 1 of the 2 available categories, which may lead to a low degree of misclassification. Any misclassification in self-reported sex would likely bias our estimates toward the null.
Although this last sentence is not totally true (if all transgenders labelled themselves as gender A, and they had non-random performance, it could bias the findings in favor/against gender A), it probably is true in the setting of the study, where you can assume transgender doctors label themselves as one or the other sex with a similar proportion, and have either male or female-level performance. Plus there aren't very many.
Heteronormative refers to the assumption that being heterosexual is the normal or preferred sexual orientation. Since no one has brought up the topic of sexual orientation, you're probably trying to use the word cisnormative here.
Edit: Added a new line for better readability
Not necessarily, no.
> ... you can be any gender you like or believe without it effecting your professional competence.
Yep, but if one gender has a natural advantage then we should absolutely research into why, shouldn't we?
This time it is about women doing better, other times it is about men.
How about we stop saying sexism every time? Both when men seems to thrive/do better in certain jobs and when women do?
Edit: yelling->saying