Vanderbilt does grade inflation, but in STEM, not as much, it grades like the following classes of schools which are considered less generous than many peers: WUSTL, Duke, Rice, Emory, USC, Berkeley, UCLA, Cornell, Northwestern, and Chicago (maybe Columbia?), Hopkins. These all typically curve (with professors that choose to give fairly difficult exams-talking 50-70 or worse averages. Sometimes it is the caliber of the test and sometimes it is the teaching, but regardless, they curve when this happens) or have averages (for profs. that give not particularly difficult but trick or challenging enough to yield exam averages below say, 80-85,and they simply do not curve at all…this pattern seems more common at Vanderbilt so it means you have little room for error with most professors if you want a strong grade. Again, exceptions seem to be some of the math and physics sequences taken by some pre-healths but at other schools where those give pretty hard exams. At other schools, it is usually chemistry and even biology that have many professors who give the exams loaded with questions that require higher-ordered thinking so they tend to yield lower averages than normal.) pre-med STEM cores to either C+/B- or B-/B at best. The only issue with WUSTL is that its pre-med cores, like some super elites are unusually difficult in terms of the exams written and level of material covered. Vanderbilt’s score vs. GPA breakdown looks more like the other schools than they do WUSTL.
It is also partially major dependent. Like neuroscience (neurofolks at some schools are required to have a solid physics background and chemistry, all of that, so neuro majors typically have decent exposure to all major STEM disciplines in a fairly short amount of time) folks and those in the physical sciences (which typically have more stringent grading even beyond intro. courses) are known to score well on the MCAT relative to other sciences or majors do to the focus on problem solving in a majority of courses, however, often it comes at a GPA penalty, and this is especially at schools known for really challenging courses or instructors in such depts. In general physical science students are already competing with more well-prepared than normal STEM students (who are perhaps looking to go into that field and thus are not pre-health. Sometimes this means they invest less time in getting the grade but it also often means that many will invest lots of time into the material without really thinking about the grade as much…as they have talent in it or enjoy it a lot. It is hard to compete with higher numbers of intrinsically motivated learners) and then the professors in such depts are managing to find ways to even challenge the top among them.