Your exam example exemplifies that you don't or won't understand the issue. You have a bunch students take the exact same exam in your contrived example.
In the case of EMA a whole bunch of companies are taking different exams across many categories of topics all at the same school. Several taking the Cancer, Cardiovascular, Dermatology, others in Endocrinology etc. etc. and several in Neurology of which few would be related to dementia. Looking across all those very different exam topics we get an overall conflated pass rate, which will not reflect the pass chances of one specific student in one sub-category exam.
In our case the student has proven very erratic with her homework often failing to hand it in or when handed in it is full of shortcuts and unsubstantiated conclusions, which does not bode well for her final exam results.
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