The PCORnet Bariatric Study compared benefits and risks of the three most common bariatric surgery procedures—Roux-en-y gastric bypass, adjustable gastric banding, and sleeve gastrectomy. The observational study used electronic health record (EHR) data for over 65,000 patients from 41 participating healthcare organizations across the country. Data were collected through the PCORnet distributed research infrastructure from several clinical research networks (CRNs), including REACHnet. Results and publications are available on the study page on PCORI’s website.