Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Registration years of the trials. (A) First registration year of the trials for each disease. (B) Registration year of the trials and their phases (21,251 trials with phase information). Cases where more than one phase existed per trial were multi-counted (for example, in a case where Phase 1 and Phase 2 existed per one trial, two trials were counted.).
