Combination Codes and Mapping to HCC Categories




I recently received an inquiry from a coder and she provided the following image:

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The coder wanted to know why the same ICD-10-CM code would map to two different HCC codes. This is a great question!

There are over 10,000 ICD-10-CM codes that map to one or more of the 83 HCC codes included in the 2019 CMS-HCC Risk Adjustment Model (Version 23). A code can map to more than one HCC as ICD-10-CM contains combination codes (i.e., one code can represent two diagnoses or a diagnosis with a complication). This model will be used in calculating a Medicare Advantage (MA) member’s risk score and needs to take into consideration the value of the combination codes.

The column headers are what you need to watch. HCC 160 is not a payment HCC for CMS-HCCs V23 (see tables below where it has dashes for CMS-HCC Model Category V23 for 2019 Payment Year) but is a payment HCC for PACE/ESRD beneficiaries. So, if you were coding for a PACE/ESRD program that is being reimbursed under Model V21 for payment year 2019, you would use HCC 160. If the PACE/ESRD program was being paid under Model V23, you would use HCC 158.

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Here is another example: ICD-10-CM code E1152 maps to three HCCs: 18, 106 and 108 for Model V23 CMS-HCC and are payment HCCs for CMS-HCC Model V23 for 2019 payment year. In this situation, you would use all 3 and their corresponding coefficients (if you do not already have these HCCs in the patient’s profile) to calculate the RAF. This accommodates the risk associated with the combination codes for this condition.

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For your reference: The most current model is Version 23. Here is the URL to the HCC code map for Model 23:

Special thanks to my colleague, Donna Malone, who helped clarify this nuance!


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About the Author

Rose Dunn
Rose Dunn is the Chief Operating Officer at First Class Solutions, Inc., a healthcare information management leader since 1988. Rose is the author of “The Revenue Integrity Manager’s Guidebook” available from the National Association of Healthcare Revenue Integrity and other books on Coding Management and Auditing from HCPro. She engaged herself in ICD-10 more than 10 years before it was implemented. She is assisting Libman Education in the development of an HCC educational program. Rose holds a BS and MBA from Saint Louis University.

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