well, call me Johnny Come-Lately, but I have to put in my 2 pence, just the same.
you see, in the medical field, or at least the area that I know of, there is a vast chasm of difference between Accident and Negligent.
shewt, I took a class in medical legalese, and one chapter, all by it's lonesome, was dedicated to Negligence.
basically, an accident meant you didn't mean to do it, Negligence meant a concerted effort on the part of the person in question to disregard.
case study #1: A nurse (no, I'm not bashing on nurses

) grabs the wrong syringe, and administers the wrong medication. A or N?
In this particular case, it's an accident, and here's why:
He/She did not intend to give the wrong medication, true, but that has no play here. There are safeguards in place to help insure things like this don't happen, sure. The nurse
did not willfully ignore those safeguards, in this case. He/She merely grabbed the wrong syringe.
If the patient is injured, the nurse is still held accountable (disciplinary action, lawsuit...), but they are not charged with a crime.
case study #2: After repeated urgings by a CNA, a nurse does not check on a patient, and they have a sudden Vital Sign crash (cardio, or pulmonary, doesn't matter).
A or N?
This one is Negligence. I actually saw this one (in a land far, far away, no where near where I work now

). A nurse had not checked on a particular patient in hours upon hours. now, this sometimes happens when vitals are stable, patient's sleeping yadda yadda. On this particular floor, patients typically get fooled with every two hours.
so, you have a Nurse Tech (CNA) telling the RN that X Patient is having X condition, every two hours (give or take a little bit). the RN ignored the Tech, and continued to read her book.
these little examples are pretty easy, and off the top of my head. However, we don't always get all the facts up front.
wise man once said, "There's more than meets the eye."
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