FDA trials follow this approach. If something bad happens it’s logged as an adverse event; if they croak it’s a serious adverse event (SAE).

So if you have a treatment for moles, and a patient (trial participant) has a mole on their back treated and then falls down the stairs or is run over by a trolley the agency wants you to do an analysis to see if the treatment might have had something to do with getting run over or not taking the lift.

Note: this is not an exaggeration. I have written phase I and phase II clinical trial protocols earlier in my career.