Match Rates Between Home Health Assessment and Medicare Claims Data.

Area of Science:

• Health Services Research
• Data Analytics
• Public Health

Background:

• The Outcome and Assessment Information Set (OASIS) is vital for home health quality assessment.
• Accurate linkage of OASIS data with Medicare enrollment and claims is crucial for utilization monitoring and payment policy.
• Preliminary data indicated a potential decrease in OASIS-beneficiary match rates starting in 2019.

Purpose of the Study:

• To quantify the annual match rates between OASIS assessments and Medicare enrollment.
• To assess the annual match rates between OASIS assessments and fee-for-service (FFS) home health claims.
• To analyze these match rates from 2017 through 2023.

Main Methods:

• A cohort study utilizing 100% of OASIS assessments from 2017-2023.
• Linking OASIS data to the Master Beneficiary Summary File (MBSF) and FFS home health claims.
• Analyzing the proportion of OASIS assessments matched to beneficiaries and FFS claims matched to OASIS assessments.

Main Results:

• The proportion of OASIS assessments linked to a Medicare beneficiary declined from 89.8% in 2017 to 76.4% in 2023.
• The match rate of FFS claims to an OASIS assessment decreased from 96.8% to 73.9% over the study period.
• By 2023, all state-level FFS claims to OASIS assessment match rates fell below 90%.

Conclusions:

• A reduced ability to accurately link OASIS assessments to Medicare beneficiaries and claims exists.
• Researchers must exercise caution when interpreting findings from linked Medicare claims and OASIS data.
• Addressing these data linkage issues with Centers for Medicare & Medicaid Services (CMS) is necessary for reliable research and policy.