CoRe Comorbidity Files

The CoRe Comorbidity Files include the output from running the 2021 version of the Comorbidity SAS Macro, which combines diagnosis information listed on the Medicare BASE utilization Files: for the ABFF cohort - in-patient hospital claims (MedPAR), out-patient hospital claims (Outpatient), and individual provider claims (NCH); and for the MA cohort - in-patient hospital encounters (Inpatient), out-patient hospital encounters (Outpatient), and individual provider encounters (Carrier). The rule-out option that requires two or more instances (claims or encounters) listing a condition at least 30 days apart is also applied. Additionally, for the MA cohort files, the comorbidity variables are created based on 1. all encounter records and 2. encounter records excluding chart reviews (CLM_CHRT_RVW_SW= 'Y') and health risk assessments (procedure codes= G0438; G0439; G0402; or 99341-99345, 99347-99350 AND place of service= 04, 12, 14, 16, or 33).

There are two assessment windows for the CoRe Comorbidity Files:

• CoRe Comorbidity Prior to Cancer Diagnosis File summarizes the presence of all comorbidities assessed in the Comorbidity SAS Macro, as documented in the claims or encounters during the 12 months prior to each cancer diagnosis (excluding the month of diagnosis), respectively, among persons included in the ABFFS cohort (i.e., continuously enrolled in Medicare fee-for-service Parts A and B) or MA cohort (i.e., continuously enrolled in Medicare Advantage/Part C).
• CoRe Comorbidity Post Cancer Diagnosis File summarizes the presence of the comorbidities, as documented in the claims or encounters during specified time intervals after cancer diagnosis (e.g., months 1-12, 13-24, 25-36, 37-48, 49-60 and 61+), respectively, among persons who are included in the ABFFS cohort or MA cohort. The cohort exit date (e.g., Medicare enrollment status change, subsequent cancer diagnosis, end of data, or death) is also listed.
  • Note: if a person exits the ABFFS or MA cohort within a specified time interval, the comorbidity measures will still be assessed based on the available data. Date of cohort exit and reason for cohort exit are available in the data; users can decide how to handle comorbidity measures when a person was not enrolled for the full time interval.

The CoRe Comorbidity files include Yes/No indicator variables for each comorbidity assessed by the macro during each time period, as well as the Charlson and NCI Comorbidity scores. The Comorbidity Files are created at the tumor-level with each record referencing a specific cancer diagnosis (e.g., the tumor sequence number is listed and then the presence of the comorbidities are assessed relative in time to that cancer diagnosis).

Access to the CoRe files is granted through the SEER-Medicare application process.