Patient comes in for a hospital f/u diagnosed with a concussion. There is no documentation in the visit note as to how it happened but it is very clear in the hospital notes. I have always been taught that a note must stand alone for coding so I queried my provider and asked her to please review as external causes were not documented. She does not feel she has to document this. Does anyone have any documentation they can share regarding this or am I incorrect to query my physicians when this happens?