Claims Data Linked to Hospital Registry Data Enhance Evaluation of the Quality of Care of Breast Cancer

Background: Complete treatment data is central to evaluation and improvement of cancer care quality. Cancer registries vary in completeness of radiation (RT), chemotherapy (CT), and hormone therapy (HT) data. Administrative claims from health payers may supplement these registries. This study assesses the ability to link private payer claims to the National Cancer Data Base (NCDB) and the extent of additional treatment data identified in claims.

Methods: Claims for patients with breast cancer surgery from one payer in Western New York (WNY) were matched with NCDB for participating hospitals for 2001-2003 using available identifiers (reporting hospital, gender, birth date, ZIP code). Claims were analyzed for breast and axillary surgery, RT, CT, and HT, and compared with treatment recorded in the NCDB.

Results: Four hundred seventy women had claims for breast cancer surgery and 439 (91%) matched to the NCDB. Seventeen had duplicate/incomplete records. Non-matches included cases with surgery for cancer recurrence. Among 422 evaluable cases, stage was 0: 9%; I: 49%; II: 33%; III: 7%; and IV: 2%. Claims and registry were highly concordant for surgery. Registry identified RT, CT, and HT in 38%, 47%, 18%, respectively, of treatment reported in claims. Claims also provided information on drugs used and treatment duration.

Conclusions: The NCDB can be matched with private payer claims using available identifiers. Registry data in this convenience sample of hospitals did not include a substantial fraction of outpatient data identified by claims. Private payer claims may help enhance the completeness of NCDB treatment information.