I recently prevented myself from taking on at least 10 micromorts of risk (and an increased copay) by noticing a medical error before undergoing a procedure.

While I'd rather not go into the exact details of my medical history, I'll say that the procedure that I was supposed to (and did) undergo didn't require anesthesia, and was less invasive than the procedure that the hospital staff would have performed otherwise, which would have required anesthesia. I'm using 10 micromorts as an estimate of the risk I avoided taking on, because a quick Google search suggests that that's the average (though ostensibly age-independent) risk incurred by undergoing anesthesia.

The surgeon/diagnostician who was in charge of my case later claimed that he would have noticed the error before he began working on me. Regardless, taking an active role in my medical care felt nice.