Q: Can you summarize how MS-DRG grouper logic works?
A: The first step in grouping an MS-DRG is the assign the case to a major diagnostic category (MDC). This is done by classifying the principal diagnosis into one of 25 MDCs based on body system and case similarity. The only exception is cases with organ transplantation, tracheostomy, or CAR T-cell therapies, which are assigned to a pre-MDC, regardless of the principal diagnosis code.
Next, the procedure codes are analyzed to see if they are classified as medical or surgical. The IPPS logic includes classification of each procedure code as an O.R. procedure (surgical) or non-O.R. procedure (medical). This process result narrows MS-DRG assignment to a tier group.
The last step is to analyze the secondary diagnoses for complications and comorbidities (CCs) and major CCs (MCCs).
Q: Where can we find the list of MS-DRGs and relative weights for FY 2023?
A: The complete list of MS-DRGs with relative weights can be found in Table 5, as part of the IPPS final rule. This table can be downloaded in Excel format in a zip file from CMS’ website: https://www.cms.gov/medicare/acute-inpatient-pps/fy-2023-ipps-proposed-rule-home-page#Tables
Q: What happens with the new ICD-10-CM/PCS codes for the MCE logic?
A: The final rule includes details about applying MCE edits to the new codes, as appropriate. For example, for FY 2023, the new external cause codes for e-bikes have been added to the MCE for unacceptable principal diagnosis and the new obstetrical codes have been added to the female-only list.
Kristi Pollard, RHIT, CCS, CPC, CIRCC, AHIMA-Approved ICD-10-CM/PCS Trainer
Kristi also performs DRG and APC audits and is known for her vast knowledge on coding vascular interventional radiology procedures. Kristi has an extensive background in coding education and consulting and is a national speakers on topics related to ICD-10 and CPT coding as well as code-based reimbursement.