Integrating Electronic Medical Records and Claims Data for Influenza Vaccine Research

Real-world evidence (RWE) increasingly informs public health and healthcare decisions worldwide. A large database has been created ("Integrated Dataset") that integrates primary care electronic medical records with pharmacy and medical claims data on >123 million US patients since 2014. This article describes the components of the Integrated Dataset and evaluates its representativeness to the US population and its potential use in evaluating influenza vaccine effectiveness. Representativeness to the US population (2014-2019) was evaluated by comparison with demographic information from the 2019 US census and the National Ambulatory Medical Care Survey (NAMCS). Variables included in the Integrated Dataset were evaluated against World Health Organization (WHO) defined key and non-critical variables for evaluating influenza vaccine performance. The Integrated Dataset contains a variety of information, including demographic data, patient medical history, diagnoses, immunizations, and prescriptions. Distributions of most age categories and sex were comparable with the US Census and NAMCS populations. The Integrated Dataset was less diverse by race and ethnicity. Additionally, WHO key and non-critical variables for the estimation of influenza vaccine effectiveness are available in the Integrated Dataset. In summary, the Integrated Dataset is generally representative of the US population and contains key variables for the assessment of influenza vaccine effectiveness.