Prior auth is the denial everyone fights. Downcoding is the one nobody sees — a payer quietly pays you for a 99213 when you documented a 99214. Illinois just passed a law saying a human has to sign each one. Here's what one signature is worth, across 60 real Medicare geographies.
In CY2024, Medicare's national allowed amount was $117.36 for a moderate-complexity established-patient visit (99214) and $83.79 for the low-complexity one (99213). The downcode isn't a rejection you can appeal on sight — it's a $33.57 leak, one line at a time, on a visit you already worked and documented.
Horizontal: how often a reporting geography bills the moderate-complexity 99214 instead of the 99213 (its "coding intensity"). Vertical: what a single downcode costs there, in allowed dollars. Dot size is 99214 volume. It is tempting to read the right-hand dots as "up-coders" a payer should target — so drag the minimum-volume floor and watch the tidy outliers turn out to be tiny territories with a few hundred visits.
Illinois now requires a "natural person" following current AMA CPT guidelines to make or review each downcode, gives physicians a 90-day dispute window, and bans blanket algorithmic knock-downs. That's a paper trail with statutory teeth in one state — and a template the other 49 can copy.
mimi_ws_1.datacmsgov.mupphy_geo, CMS Medicare Physician & Other Practitioners by Geography and Service, CY2024 release (mimi_src_file_date = 2024-12-31); query 6a57310f182d44503158a30a / report. It sums tot_srvcs and service-weighted avg_mdcr_alowd_amt for 99213/99214 by reporting geography. Medicare FFS is a neutral coding-mix baseline—not commercial claims, an observed downcoding rate, or evidence of improper coding—and excludes Medicare Advantage. The slider is a modeling assumption.