Mahmood Ahmad
Tahir Heart Institute
author@example.com

CT.gov Modality Sponsor Repeaters

Which sponsors carry the biggest missing-results backlogs once older CT.gov studies are split by intervention family rather than ranked in one pooled sponsor table? We analysed 249,507 eligible older closed interventional studies from the March 29, 2026 full-registry snapshot and linked sponsors to intervention-family labels from the registry extract. The project compares sponsor-level no-results counts, no-results rates, ghost-protocol rates, and visible shares within drug, device, procedure, behavioral, biological, and dietary-supplement study families. In drug studies, GlaxoSmithKline carried 1,033 missing-results studies, while Cairo University led device studies with 205 records. Procedure studies led by Cairo University reached 97.3 percent no results, Maastricht University Medical Center led dietary-supplement backlogs with 154 studies, and UCSF led behavioral backlogs with 317. Sponsor repeaters therefore change sharply by modality, meaning whole-registry rankings hide intervention-specific clusters of silence that recur inside particular treatment families. Sponsor names and intervention labels are registry-entered fields and do not adjudicate parent-company structure, collaborations, or off-platform dissemination.

Outside Notes

Type: methods
Primary estimand: Sponsor-level 2-year no-results counts within intervention families among eligible older CT.gov studies
App: CT.gov Modality Sponsor Repeaters dashboard
Data: 249,507 eligible older closed interventional studies grouped by extracted intervention-family labels and lead sponsor
Code: https://github.com/mahmood726-cyber/ctgov-modality-sponsor-repeaters
Version: 1.0.0
Validation: FULL REGISTRY RUN

References

1. ClinicalTrials.gov API v2. National Library of Medicine. Accessed March 29, 2026.
2. Zarin DA, Tse T, Williams RJ, Carr S. Trial reporting in ClinicalTrials.gov. N Engl J Med. 2016;375(20):1998-2004.
3. DeVito NJ, Bacon S, Goldacre B. Compliance with legal requirement to report clinical trial results on ClinicalTrials.gov: a cohort study. Lancet. 2020;395(10221):361-369.

AI Disclosure

This work represents a compiler-generated evidence micro-publication built from structured registry data and deterministic summary code. AI was used as a constrained coding and drafting assistant for interface generation, packaging, and prose refinement, not as an autonomous author. The analytical choices, interpretation, and final outputs were reviewed by the author, who takes responsibility for the content.