Probably a lot because the metric isn't whether you did the work commensurate with the payment you received, it's whether you've DOCUMENTED everything to their liking.
On page 3 of the CMS "Evaluation and Management Services Guide" in the first section labeled "Medical Record Documentation", which is the first substantive page of the Guide, they quote the adage, "if it isn't documented, it hasn't been done."
They go on to state on that page:
Clear and concise medical record documentation is critical to providing patients with
quality care and is required in order for providers to receive accurate and timely
payment for furnished services. Medical records chronologically report the care a
patient received and are used to record pertinent facts, findings, and observations about
the patient’s health history. Medical record documentation assists physicians and other
health care professionals in evaluating and planning the patient’s immediate treatment
and monitoring the patient’s health care over time.
Health care payers may require reasonable documentation to ensure that a service is
consistent with the patient’s insurance coverage and to validate:
❖ The site of service;
❖ The medical necessity and appropriateness of the diagnostic and/or therapeutic
services provided; and/or
❖ That services furnished have been accurately reported.