Healthcare Solutions | ICD-10 Code Mapping
ICD-10 Code Mapping
The Financial Risk When Relying on DRG-Based Reimbursement
For healthcare organizations who depend on DRG (diagnosis-related group) codes for reimbursement, the transition from ICD-9 to ICD-10 carries significant risks. There are no one-to-one mapping relationships between ICD-9 and ICD-10 codes, and reimbursements could vary dramatically depending on how DRG groupers are mapped in ICD-10 compared to ICD-9. They could be very different.
The Centers for Medicare and Medicaid Services (CMS) uses a diagnosis-related group (DRG) structure for reimbursement to providers called the Medicare Severity Diagnosis Related Group, or MS-DRG. DRGs were developed as a means to classify hospital cases into 999 groups of patient cases with similar conditions that are likely to use the same level of hospital resources.
The DRG for a certain claim is selected based on the ICD code(s) present on the patient claim. Therefore, the reimbursement on every claim depends on the assignment of diagnosis codes to particular DRGs. And migration to ICD-10 could result in significant over- or underpayment when using DRG-based reimbursement.
Figure 1 shows an example where the mapping from ICD-9 to ICD-10 might result in an overpayment or underpayment to the provider.
ICD-9 Code 6149 is categorized under MS-DRG 759. When converting to ICD-10, ICD-9 Code 6149 can be mapped to two different ICD-10 codes: N735 or B3749. These map to DRG 759 (same as ICD-9) and 690, respectively. The resulting payment in the second case is about $6,000 more than what would have been paid before the ICD-10 transition.
Each mapping carries a certain level of risk and can be classified as high risk or low risk, based on the variations in reimbursements created by mapping to ICD-10.
Figure 2 shows examples of a high-risk mapping and a low-risk mapping.
The financial risk created by such mapping must be assessed by all entities that interact with the Medicare Inpatient Prospective Payment System.
Conclusion
Based on the above examples, it’s easy to draw a significant conclusion:
For health plans, it’s imperative that they identify and partner with high-risk providers— those most likely to use codes at high risk for reimbursement variances—to alleviate risks in DRG-based reimbursements.
In order to remediate for the risks associated with DRGbased reimbursement, health plans will need to assess their ICD-9 to ICD-10 maps and corresponding DRG groupers, and prioritize remediation efforts towards the high-risk mappings. The scope of this remediation can vary based on the health plan’s provider network and the incoming claims.
For example, when reviewing a midsize health care plan’s data, Edifecs determined that approximately 80% of the MS-DRG-based ICD-9 claims led to the same MS-DRG based grouper when translated via GEMs to the ICD10 code. The claims in this 80% would be considered low risk and prioritized accordingly.
However, 18% of the plan’s MS-DRG-based ICD-9 claims translated to different (or multiple) MS-DRG grouper(s) after translating to ICD-10, posing great financial risk to the plan.
The scope of remediating DRG-based reimbursement systems for mapping risk can be daunting for health plans with a huge provider network. The ideal approach would focus efforts on those providers that send claims containing DRGs that pose the greatest risk to reimbursement systems. This can be done by analyzinghistorical claims on high-risk ICD-9 codes, claim volumes and billed amounts.
In the above example, this would be equivalent to identifying the specific providers that send all or most of the 18% high-risk ICD-19 codes. Once these providers are identified, health plans need to create a streamlined process for collaborating with them to create a shared understanding of DRG-based reimbursement expectations and testing the high-risk codes for financial risks and variances. Identification of specific providers based on risk profiles and collaborating on DRG groupers is therefore the best approach to remediating for mapping-based risk in claim reimbursements.