I wonder why gender is a factor. It suggests to me that the model is reflecting the biases of the data set. That's understandable, although the authors don't try to correct for that.

@AzorAhai MD is, in theory, a broader term, as there are physicians and surgeons (an older but still observed).

I would write "completed medical training (MD) in Mexico". To the public writing MD or Dr. (in a clinical context) means "can function like a doctor I know or one on TV". Residents, for example, are MDs that may have no license or limited licenses depending on the state. Once finished residency to work as an attending physician in a state you must be licensed with that Board, which certifies that you have taken and passed all necessary qualifications. (Source = I am a practicing MD PhD physician)

Lecture. Such an item might help the "Teaching Activities" part of a CV. You may choose to leave it out, depending on who will be reading the CV.