Measurement of skeletal related events in SEER-Medicare: a comparison of claims-based methods

Abstract

BackgroundSkeletal related events (SREs) are common in men with metastatic prostate cancer (mPC). Various methods have been used to identify SREs from claims data. The objective of this study was to provide a framework for measuring SREs from claims and compare SRE prevalence and cumulative incidence estimates based on alternative approaches in men with mPC.MethodsSeveral claims-based approaches for identifying SREs were developed and applied to data for men aged [greater than or equal to] 66 years newly diagnosed with mPC between 2000 and 2009 in the SEER-Medicare datasets and followed through 2010 or until censoring. Post-diagnosis SREs were identified using claims that indicated spinal cord compression (SCC), pathologic fracture (PF), surgery to bone (BS), or radiation (suggestive of bone palliative radiation, RAD). To measure SRE prevalence, two SRE definitions were created: ‘base case’ (most commonly used in the literature) and ‘alternative’ in which different claims were used to identify each type of SRE. To measure cumulative incidence, we used the ‘base case’ definition and applied three periods in which claims were clustered to episodes: 14-, 21-, and 28-day windows.ResultsAmong 8997 mPC patients, 46 % experienced an SRE according to the ‘base case’ definition and 43 % patients experienced an SRE according to the ‘alternative’ definition. Varying the code definition from ‘base case’ to ‘alternative’ resulted in an 8 % increase in the overall SRE prevalence. Using the 21-day window, a total of 12,930 SRE episodes were observed during follow up. Varying the window length from 21 to 28 days resulted in an 8 % decrease in SRE cumulative incidence (RAD: 10 %, PF: 8 %, SCC: 6 %, BS: 0.2 %).ConclusionsSRE prevalence was affected by the codes used, with PF being most impacted. The overall SRE cumulative incidence was affected by the window length used, with RAD being most affected. These results underscore the importance of the baseline definitions used to study claims data when attempting to understand relevant clinical events such as SREs in the real world setting.

Utilization of novel systemic therapies for multiple myeloma: A retrospective study of front‐line regimens using the SEER‐Medicare data

“…We used these data to identify patient‐level clinical and demographic characteristics and clinical events such as administration of systemic therapies. The SEER‐Medicare dataset is regarded as generalizable to the elderly cancer patients …”

Risk of skeletal related events among elderly prostate cancer patients by site of metastasis at diagnosis

“…ADT is the mainstay of treatment, and in fact represents the first line of treatment for M1 prostate cancer patients. Despite this, remarkably, 25.8% of the M1 cohort did not have claims for ADT receipt, a figure that is not inconsistent with what has been reported previously by others . Claims reflecting all four SRE subcomponents are significantly less in the non‐ADT group than in the corresponding ADT group (Table ).…”

Do skeletal-related events predict overall survival in men with metastatic castration-resistant prostate cancer?

“…One study noted that there is no billing code specifically for SREs, no common framework for measuring SREs using these codes, and dates are not always accurate. 18 Thus, SRE prevalence can vary greatly depending on the codes used and studies may underestimate or misclassify SREs. However, in our study, we conducted a thorough review of the medical records using the common definition of SRE to accurately determine date and type of SRE.…”