When converting from paper, we had the staff pull the paper charts for the scheduled patients for the week. Then in free time, evenings, weekends, we made a new encounter, called it "Initial data entry" for the CC, put in all the old stuff including diagnosis codes, vacciations, pmh, fh, sh, and anything else we wanted, signed off and did not enter a charge.
It was a lot of work, but it reduced the degree to which each initial EHR patient visit turned into a new patient visit which is what happened if we waited until we saw the patient. Our population just had way too many problems we needed to track to get away with any of that in a 15 minute slot. It was bad for 2-3 months, easier after that, and gone after a year.
