ClinicalTrials.gov is a registry and results database of publicly and privately supported clinical studies of human participants conducted around the world. ClinicalTrials.gov is a resource provided by the US National Library of Medicine.
The Clinical Trials Search Portal provides access to a central database containing the trial registration data sets provided by 17 international registries. It also provides links to the full original records.
The ISRCTN registry is a primary clinical trial registry recognised by WHO and ICMJE that accepts all clinical research studies (whether proposed, ongoing or completed), providing content validation and curation and the unique identification number necessary for publication. All study records in the database are freely accessible and searchable.
The Trials Register of Promoting Health Interventions (TRoPHI) is unique in its focussed coverage of trials of interventions in health promotion and public health worldwide. It covers both randomised and non-randomised controlled trials and currently contains details of over 7,750 trials.