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 FFS Files: in-patient hospital claims (MedPAR), out-patient hospital claims (Outpatient), and individual provider claims (NCH). The rule-out option that requires two or more individual provider and/or outpatient claims listing a condition at least 30 days apart is also applied.

There are two 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 during the 12 months prior to each cancer diagnosis (excluding the month of diagnosis), among persons included in the ABFFS cohort (i.e., continuously enrolled in Medicare fee-for-service Parts A and B).
• CoRe Comorbidity Post Cancer Diagnosis File summarizes the presence of the comorbidities, as documented in the claims during specified time intervals after cancer diagnosis (e.g., months 1-12, 13-24, 25-36, 37-48, 49-60 and 61+) among persons who are included in the ABFFS cohort. The ABFFS cohort exit date (e.g., date discontinued enrollment in Medicare fee-for-service, Parts A or B; or death) is also listed.
  • Note: if a person exits the ABFFS 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.

Both 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.