If my doctor has a patient that he has seen at the hospital (99233, etc.) only, and then that patient schedules an initial visit at our office to become an established patient here, should I bill 99203 (as all the NP/initial visit parameters are met/performed, and technically the patient has never been to our office) or 99213 (as technically, the doctor HAS seen the patient within the last three years)? This may be the simplest/most obvious/idiotic question ever, but I would really appreciate some clarification on this!