I cannot recommend this recent Atlantic piece by David Epstein more strongly. It absolutely captures the problem of overtreatment and the pressures that fuel this source of medical waste and patient harm. Plus, it does a great job of explaining the number needed to treat and the number needed to harm. Read the original article here.
The audio version is here, for those who prefer to listen instead of read (I did both):
Emergency Physician, Educator, Researcher, interested in the microbiome, evolution, and medicine