Below are lists or registries of current, ongoing and completed clinical trials. To find published clinical trials, databases such as the Cochrane Library, PubMed and Embase should be searched.

• Canada Trials (a searchable database of Clinical Research Trials that are actively enrolling patients in Canada)



• CenterWatch Clinical Trials Listing Service



• Clinical Study Results (A repository of clinical study results sponsored by the Pharmaceutical Research and Manufacturers of America)



• ClinicalTrials.gov (A searchable/browsable database of clinical trials) (an NIH initiative)



• CRISP (A searchable database of federally funded biomedical research projects conducted at universities, hospitals, and other research institutions in the U.S.)



• Current Controlled Trials Register International Standard Randomised Controlled Trial Number Register of ongoing controlled trials - free registration



• Eli Lilly and Company Clinical Trial Registry (This site contains information about clinical trials sponsored by Eli Lilly and Company)



• GlaxoSmithKline Clinical Trial Register (Provides an accessible repository of data from GSK-sponsored clinical trials)



• National Cancer Institute of Canada Clinical Trials Group (Clinical trials in cnacer and supportive care led by the NCIC Clinical Trials Group)



• National Cancer Institute (US) Clinical Trials Database (Includes ongoing and completed cancer trials, as well as information on cancer prevention, diagnosis and treatment.)



• National Research Register (U.K.) A database of ongoing and recently completed research projects funded by, or of interest to, the United Kingdom's National Health Service (NHS).



• Ontario Cancer Trials (Search the database of cancer trials in Ontario)



• Trials Central (This international register lists clinical trials in different medical specialities.)



• Warren Grant Magnuson Clinical Center (National Institutes of Health) lists over 1,000 NIH current and ongoing clinical research studies

James Lind Library Documenting the evolution of fair tests of medical treatments.