We now have four years of allergy/immunology Medicare E&M coding data following the E&M rule change in 2021, with E&M codes based on time or medical decision-making. The trend is clear: allergists’ coding patterns have continued to shift in favor of higher E&M codes over the past four years.
Medicare publicly reports specialty-specific E&M utilization data each year, which they use to identify providers who are overcoding. But this data can also tell us how allergy/immunology E&M coding patterns change over time, as well as help you see how your coding distribution for E&M services compares to other allergists.
2020-2024 Medicare E&M code usage for allergy/immunology is summarized below. Coding pattern shifts have been gradual as allergists learned how to incorporate the new rules. However, there has been a clear increase in level 4 coding and a corresponding decrease in level 3 coding for both new and existing patients over the past three years – but the shift for existing patients has been most significant. For new patient visits, level 4 visits increased 5 percentage points to just under 62% in 2024. Level 3 visits decreased the same amount to about 29%. The most common code used by allergists in all four years was a level 4, with level 3 being the next most common.
Allergy/Immunology Medicare E&M Distribution –
New Patients
2020 – 2024
| New Patient E&M Code | 2024 Utiliz. % |
2023 Utiliz. % |
2022 Utiliz. % |
2021 Utiliz. % |
2020 Utiliz. % |
|---|---|---|---|---|---|
| 99202 | 0.7% | 1.0% | 1.1% | 1.6% | 2.2% |
| 99203 | 28.6% | 29.8% | 31.2% | 32.2% | 34.1% |
| 99204 | 61.8% | 60.8% | 59.9% | 58.5% | 57.0% |
| 99205 | 8.8% | 8.4% | 7.8% | 7.7% | 6.7% |
| Total | 100.0% | 100.0% | 100.0% | 100.0% | 100.0% |
| Source: Medicare Part B Utilization CY2021 E&M Codes by Specialty, Medicare Part B Utilization CY2020 E&M Codes by Specialty and CMS Physician/Supplier Procedure Summary | |||||
Coding shifts for existing patient visits were more marked. Level 4 usage increased by 10 percentage points to 50% in 2024 and is clearly the most common E&M code used by allergists. Level 3 coding dropped 8.6 percentage points to 39.8% in 2024. Levels 1, 2 and 5 continue to be used infrequently – but we are seeing a small increase in coding for level 5 and slight decreases in coding for levels 1 and 2.
Allergy/Immunology Medicare E&M Distribution –
Existing Patients
2020 – 2024
| Existing Patient E&M Code | 2024 Utiliz. % |
2023 Utiliz. % |
2022 Utiliz. % |
2021 Utiliz. % |
2020 Utiliz. % |
|---|---|---|---|---|---|
| 99211 | 2.6% | 2.7% | 3.2% | 3.4% | 4.0% |
| 99212 | 3.2% | 3.7% | 4.1% | 4.6% | 4.8% |
| 99213 | 39.8% | 41.9% | 43.9% | 45.7% | 48.4% |
| 99214 | 49.9% | 47.7% | 45.0% | 42.8% | 40.0% |
| 99215 | 4.4% | 4.0% | 3.7% | 3.5% | 2.7% |
| Total | 100.0% | 100.0% | 100.0% | 100.0% | 100.0% |
| Source: Medicare Part B Utilization CY2021 E&M Codes by Specialty, Medicare Part B Utilization CY2020 E&M Codes by Specialty and CMS Physician/Supplier Procedure Summary | |||||
Is your practice seeing a similar trend in E&M coding? You may want to pull your own historical coding data from your practice management system to see how it compares to the average Medicare coding distribution for allergists/immunologists. Keep in mind, however, that every practice has a different demographic of patients, and your own experience, especially with non-Medicare patients, may not be directly comparable to the Medicare average.
If you or your billing staff needs a refresher on E&M coding based on time or medical decision-making, we encourage you to check out the College’s recently updated Coding Toolkit. We have easy-to-understand articles on the E&M coding rules, plus expert advice on many common (and not-so-common) allergy coding questions. Our Coding FAQ database should be the first place you look when you have an allergy coding question!
Special thanks to College member Robert Ellis, the CFO of the Carolina Asthma & Allergy Center, for sharing the 2022, 2023 and 2024 data cited in this article.
