CT.gov Country Sponsor Repeaters

Paper

Which sponsors hold the largest missing-results stock inside country-linked CT.gov portfolios? We analysed 249,507 eligible older closed interventional studies from the March 29, 2026 full-registry snapshot and ranked lead sponsors within selected country-linked portfolios. The project compares sponsor-level missing-results counts, no-results rates, ghost-protocol rates, and visible shares across United States, China, Egypt, Poland, Australia, and Japan footprints. In United States-linked studies, Mayo Clinic carried the largest missing-results stock at 927 studies, while Sun Yat-sen University led China with 235 and Cairo University led Egypt with 968. Poland was cleaner, with Sanofi at 47.5 percent no results and Hoffmann-La Roche at only 59 missing-results studies, while Australia and Japan also sat below China or Egypt on rate. Country-linked sponsor repeaters therefore differ sharply across national footprints, meaning the same registry backlog resolves into different institutional stories once geography is named. Country-linked sponsor tables reflect recorded study locations rather than sponsor domicile, enrollment shares, or national legal exposure.