The Devil is in the Data: A Detailed Look at MDM Changes for 2021

Medical Decision Making

Major changes are found in the 2021 Evaluation and Management guidelines.

As we enter the final quarter of 2020, I hope everyone is committed to being prepared for the 2021 evaluation and management (E&M) changes, because they’re locked in, and the focus going forward should be on education for coders, auditors, and providers.

Many articles have already been written about the implications of CPT eliminating the history and physical exam as factors in determining the E&M code level. The most important consensus among all of these is a) medical necessity still reigns supreme as the Centers for Medicare & Medicaid Services’ (CMS’s) “overarching criterion” for E&M level selection, and b) medical decision-making (MDM) will now take center stage.

I fully acknowledge that in 2021, thanks to changes in the requirements for time-based E&M coding, the amount of time documented will be another decisive factor. But that doesn’t change the fact that documentation supporting the level of medical necessity corresponding to the E&M level selected is still crucial. What’s more, time-based coding won’t apply to all encounters, but medical necessity will, and MDM is often a better proxy for medical necessity than time. The way MDM is scored under the 2021 rules is actually changing quite a bit, when it comes to the data element. So I’d like to focus on MDM, and specifically how the data piece is changing.

MDM will still have the same three elements:

  • Number and complexity of problems addressed;
  • Amount and/or complexity of data reviewed; and
  • Overall risk of complications, morbidity, and/or mortality.

Digging into the Amount and/or Complexity of Data Reviewed

Items 1 and 3 above aren’t really changing in 2021; they do receive some clarifying language, which I’ve written about in earlier articles for ICD-10monitor and RACmonitor. Item 2, the data piece, will be quite unrecognizable when compared against current 1995/1997 documentation guidelines. In 2021, there will be three categories (see related table), each describing different types of clinical data that could be documented. Category 1 is for tests and documents, but it can also include the use of an independent historian. Category 2 is unique because it changes depending on whether or not an independent interpretation of tests was documented. When no independent test interpretation is documented, Category 2 changes to assessing whether an independent historian was documented, and if so, it’s credited toward a low level of data review, supporting low medical complexity. When an independent test interpretation is done, Category 2 gets credited toward a moderate level of data review, while the independent historian element is reassigned to Category 1. If you do both, the test interpretation is credited under Category 2, and the historian under Category 1. Category 3 is simpler: it’s the discussion of patient management or test interpretation with an external provider – defined as a healthcare professional not in the same group practice or of a different specialty in the same practice.

2021 Medical Decision-Making (MDM):
Amount and/or Complexity of Data to be Reviewed and Analyzed
Code level Category 1 elements Category 2 elements Category 3 elements
No requirements
Minimal N/A N/A
Limited: Category 1 or Category 2 Limited Limited N/A
Moderate: Any single category at moderate/extensive Moderate/
Extensive: Any two categories at moderate/extensive
Source: 2021 CPT E&M Office or Other Outpatient and Prolonged Services Code and Guideline Changes


CPT®:  Subtle but Highly Impactful Change

One major change – and the CPT language explaining this subtle, so it’s easy to miss – is that in 2021, we will count each unique diagnostic or laboratory test as one point under Category 1, the category for tests and documents. So if the doctor orders a chest X-ray and knee X-ray, that goes for two points under Category 1. This is wholly different from how we do it now, where points are credited based on test modality, so two X-rays (or one X-ray and one MRI) is one point, because they’re both radiology tests.

This new way of quantifying data for MDM purposes will seem complicated at first, but you’ll get used to it, and I suspect doctors will appreciate getting credited for each unique test or order. Under the current 1995/1997 guidelines, it’s not unusual for doctors to complain, after being given their audit results, that it’s not fair to receive only one point for data review when they looked over a slew of different radiology tests. After all, from their perspective, that’s a lot of data to analyze.

As the old saying goes, the devil is in the details, and that’s why we should all be devoting some time and attention to these types of details as the Jan. 1, 2021 implementation date looms large on the horizon.

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