[sambe]

It doesn't have to instantly and directly kill somebody to be bad in aggregate.

This kind of analysis has been done, most memorably for breast cancer screening. The conclusion I recall was that it did more harm than good a few years ago (opportunity cost of unnecessary spending, pain and complications of biopsy, unnecessary mastectomy, psychological damage, etc. etc.). The follow-up tests and analysis also have an error rate and no treatment is zero cost.