Research has demonstrated associations between antibiotic use in early life and higher weight in later childhood. Lingering questions regarding this association include potential heterogeneity of treatment effects: the timing, type, and number of antibiotic exposures in early life; and differential effects of antibiotics in subgroups, such as by sex and medical comorbidities. With electronic health record (EHR) and other health care data available for large populations, the National Patient-Centered Clinical Research Network (PCORnet) provided a unique opportunity to investigate these questions and help build the research capacity of this new network. The study was led by 3 principal investigators, and the study results include data from 36 PCORnet institutions in 10 clinical data research networks (CDRNs).
