Improving Real-World Mortality Data Quality in Oncology Research: Augmenting Electronic Medical Records With Obituary, Social Security Death Index, and Commercial Claims Data

PURPOSE This study evaluated the relative improvements in mortality data capture of adding different external data to enriched electronic medical records (EMRs) for patients with melanoma. METHODS An enriched EMR database, containing structured and unstructured data, was used to evaluate the incremental mortality data capture of the following external data sources: Social Security Administration (SSA), public obituary, and an administrative open-claims database for the claims data set. Overall survival (OS) was assessed for each data set and the composite data set using the Kaplan-Meier method. RESULTS A total of 3,882 patients were included in the study. The enriched EMR data set identified 1,085 patients with a death record. The SSA data set identified 213 patients (73 unique when combined with enriched EMR) with a death record, while the obituary data set identified 1,127 patients (241 unique). The administrative claims data set identified 378 patients (73 unique) with a death record; however, all these unique patients were already accounted for in the combined SSA and obituary data set. The composite data set yielded a median OS of 13.39 years, about 4 years shorter than the enriched EMR data set alone (17.63 years). CONCLUSION When the enriched EMR data set was augmented with one external data set, the obituary data set provided the most additional value, followed by claims, and then SSA. The augmentation of all the data sources had a significant impact on the OS results compared with enriched EMR alone.