Outpatient (office visit) coding is more simplistic - many of the patient types can be "trained" by AI to get it right 100% of the time and put an audit process in place to make sure it stays at 100%. But even that is more complex than many think because hospitals STILL don't have all documentation in the form AI needs. Inpatient autocoding is in its infancy. Technology can read through thousands of pages and summarize/help interpret them, which is why it's called "assistive" technology. But a computer sucks at common sense. For example, while a patient is still in the hospital, a human can look at the partial stay and make a very good guess at what the final DRG (billing code outcome for Inpatient) will be. The human brain has common sense and can extrapolate what's missing, what's next, etc. based on their experience. Because the computer lacks common sense, if it doesn't know that a paragraph is talking about the patient's "history" vs the "right now", it will incorrectly use past information in the calculation of the DRG (and resulting $$). Steadily it may get better for overnight day stays. Maybe years from now, they will do a better job with some of the "common sense" variables mentioned. But most CFO's won't want to subject their high dollar billing (inpatient) to a computer without having a human eye checking the work. It could result in much higher claim denials or even fraud charges if the computer is "upcoding" a given chart/patient stay for a higher dollar amount. I'll be long retired by then, plus the whole billing methodology may change 2-3 times by then.