Agreement between Surveillance, Epidemiology, and End Results- and Medicare Claims-Derived Uterine Cancer Treatment Data.

BACKGROUND

Despite the prevalent use of Surveillance, Epidemiology, and End Results (SEER)-Medicare data to study uterine cancer treatment patterns and survival, concordance between SEER and Medicare claims has not been a focus of prior research. We assessed the agreement between SEER and Medicare claims, predictors of disagreement between sources, and associations between treatment (identified in SEER vs. Medicare) and survival.

METHODS

Patients diagnosed with uterine cancer between 2000 and 2019 were identified using the SEER-Medicare linked database. We calculated kappa statistics to assess the agreement between the two data sources for receipt of hysterectomy with or without bilateral salpingo-oophorectomy (BSO), hysterectomy with BSO, lymphadenectomy, external beam radiotherapy (EBRT), vaginal brachytherapy (VBT), and chemotherapy. For each treatment type, we examined temporal trends in the kappa and used multivariable-adjusted logistic regression to examine predictors of disagreement. Treatment hazard ratios in Cox proportional hazards regression models using treatment information from SEER versus Medicare were compared.

RESULTS

For each treatment, we excluded patients with unknown SEER information, resulting in variable sample sizes. Agreement was lowest for hysterectomy with BSO (kappa = 0.71) and highest for lymphadenectomy and chemotherapy (kappas = 0.85). Temporal variation was evident, with lymphadenectomy, EBRT, and VBT agreement dropping in recent years. Black race, younger age at diagnosis, high-risk histology, and advanced stage were associated with higher odds of disagreement for certain treatments. Associations between treatment identified in SEER versus Medicare and survival outcomes were similar.

CONCLUSIONS

Treatment agreement between SEER and Medicare was high.

IMPACT: Our results support the use of both data sources for uterine cancer treatment-survival analyses.