Speaking only from personal experience, medical researchers in the US may not have any training in Calculus. I'd put it at ~30% that do not. It is only taught i

Speaking only from personal experience, medical researchers in the US may not have any training in Calculus. I'd put it at ~30% that do not. It is only taught in High Schools if the child and their parents want them to take it and is not required for graduation (though this varies a lot from district to district). Depending on the major and the school, Calculus may also not be required for graduation from university. Depending on the grad-school, Calculus is also not required for a PhD. Speaking personally, I know of entire departments where Calculus is not known among the majority of the faculty members who are publishing in medicine/biology, though this is a bit rare. However, higher order Calculus like Lagrangians, Diff-Eqs, and Matrix algebra is as rare as hen's teeth among bio/medical researchers.