Information Services

Finding Clinical Trials

Suggestions of web resources and subscription databases which can be used to find clinical trials



Description: AllTrials calls for all past and present clinical trials to be registered and their full methods and summary results reported.

Subscription Databases:


Cochrane CENTRAL (Central Register of Controlled Trials) - choose "Trials - Advanced search only"

N.B. Choose "Trials - Advanced search only"
Description: Details from bibliographic databases, notably MEDLINE (approximately three-fifths of the records) and EMBASE, as well as other published and unpublished sources. Each Cochrane Review Group maintains and updates a collection of controlled trials relevant to its own area.



CINAHL Plus, MEDLINE, psycINFO: Go to Limits or Additional Limits, Publications and choose "Clinical Trials"
EMBASE: Has an Additional Limit for Clinical Trials.


Freely available web databases - National:


Description: Studies considered eligible for inclusion by the four UK Health Administrations using the Clinical Research Network.
Coverage: not clear


Description: Information about ongoing trials. Established by the National Institute for Health Research on behalf of all the UK Health Departments and with the assistance of a number of clinical research charities, research professionals and patient representatives.
Coverage: Existing trials but includes not recruiting, completed and stopped.


Description: U.S. National Institutes of Health information. Adverse event information required from September 2009.
Coverage: Launched 2008 but studies entered pre-date that.


Freely available web databases - International:


Description: Industry-sponsored clinical trials information for researchers and patients.
Coverage: 1994 onwards


Description: Springer-BioMedCentral's database of trials registered with International Standard RCT Number and for “across multiple registers”. Select “All registers” (left menu in “across multiple registers “ search) to see archive trial sources.
Coverage: 1998 onwards


Description: Information on clinical trials in European Union (EU) member states and the European Economic Area (EEA) and clinical trials which are conducted outside the EU/EEA if they form part of a paediatric investigation plan (PIP)
Coverage: 2004 onwards


PROSPERO: International prospective register of systematic reviews

Access information: Freely available

Protocol details for systematic reviews relevant to health and social care, welfare, public health, education, crime, justice, and international development, where there is a health related outcome.

Systematic review protocols on PROSPERO can include any type of any study design. Reviews of reviews and reviews of methodological issues that contain at least one outcome of direct patient or clinical relevance are also accepted.

Additional information: Produced by CRD and funded by the National Institute for Health Research (NIHR).



Description: Trial registration data sets provided by registries from around the world, incl Africa, China and India as well as Australia & New Zealand, Europe and the USA.
Coverage: mid-1990s onwards


Pharmaceutical company information:

Pharmaceutical companies may make information about trials available.