International Clinical Trials Registry Platform (ICTRP)


Audit Trail
Documentation that allows reconstruction of the course of events (from ICH E6). In relation to trial registration applies to the ability to monitor changes made to the trial registration data set after the time of initial registration.

Best Practice for Clinical Trial Registries
Best Practice for Clinical Trial Registries will document the minimum standards expected of clinical trials registries in relation to all aspects of their work. They will include, but not be restricted to, minimum standards for:

  • Minimizing (unplanned) duplicate registration of single trials
  • Validation
  • Compliance
  • Comprehensiveness
  • Databases
  • Data sharing

Central Repository
A database that contains the trial registration data sets provided by each Data Provider. It exists for searching purposes only. It is this database that is searched when using the WHO Search Portal. All items in the trial registration data set are copied from individual registries onto the Central Repository, and data is updated regularly (once each week).

Clinical Trial
For the purposes of registration, a clinical trial is any research study that prospectively assigns human participants or groups of humans to one or more health-related interventions to evaluate the effects on health outcomes. Clinical trials may also be referred to as interventional trials. Interventions include but are not restricted to drugs, cells and other biological products, surgical procedures, radiologic procedures, devices, behavioural treatments, process-of-care changes, preventive care, etc. This definition includes Phase I to Phase IV trials.

Clinical Trial Register
The formal record of an internationally agreed minimum amount of information about a clinical trial (trial registration data set). This record is usually stored in and managed using a database.

Clinical Trial Registry
The entity that houses the clinical trial register. It is responsible for ensuring the completeness and accuracy of the information the register contains, and that the registered information is used to inform health care decision making.

Data Interchange Standard
A set of rules for sending information between machines. Includes agreement and standardization on the concepts exchanged (e.g., “primary sponsor”), and agreement and standardization on the structure of the actual message that is exchanged.

Data Provider
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Multi-centre trial
A single trial conducted according to a single protocol but at more than one site (from ICH E6). These sites may be across multiple countries.

Non-Contributing Registry
A register that does not submit data, either directly or indirectly, to the Central Repository. This is because some registers may wish to be part of the Register Network but do not meet one or more of the Criteria for a Contributing Register.

Partner Registry
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Biomedical clinical trials of experimental drug, treatment, device or behavioral intervention may proceed through four phases:

  • Clinical trials test a new biomedical intervention in a small group of people (e.g., 20-80) for the first time to evaluate safety (e.g., to determine a safe dosage range and to identify side effects).
  • Clinical trials study the biomedical or behavioral intervention in a larger group of people (several hundred) to determine efficacy and to further evaluate its safety.
  • Studies investigate the efficacy of the biomedical or behavioral intervention in large groups of human subjects (from several hundred to several thousand) by comparing the intervention to other standard or experimental interventions as well as to monitor adverse effects, and to collect information that will allow the intervention to be used safely.
  • Studies are conducted after the intervention has been marketed. These studies are designed to monitor effectiveness of the approved intervention in the general population and to collect information about any adverse effects associated with widespread use.

    From NIH

Primary Registry
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Prospective Meta-Analysis (PMA)
A prospective meta-analysis (PMA) is a meta-analysis of studies (usually randomized controlled trials) that were identified, evaluated and determined to be eligible for the meta-analysis before the results of any of those studies became known. (Reference: Cochrane Handbook)

Prospective Registration
When a trial is registered in a primary registry before the recruitment of the first patient. The ICTRP database flags prospective records by comparing the 2 fields 'date of registration' of the trial and 'date of first enrolment' of patients. Prospective is when (by ICTRP standards) the year of the 'date of registration' field is prior to the year of the 'date of first enrolment' field.

A document that describes the objective(s), design, methodology, statistical considerations, and organization of a trial. The protocol usually also gives the background and rationale for the trial (from ICH E6).

Protocol Amendment
A written description of a change(s) to or formal clarification of a protocol. (from ICH E6)

Publication Bias
This is where the likelihood of publication is influenced by the direction or strength or the trial results.

The process of assigning trial subjects to treatment or control groups using an element of chance to determine the assignments in order to reduce bias. (from ICH E6)

Responsible Registrant
An appropriate representative of the trial’s primary Sponsor. The Responsible Registrant is responsible for ensuring that the trial is properly registered. The primary Sponsor may or may not be the primary funder. The responsible registrant should make every reasonable effort to ensure that a trial is registered once and only once in any one register, and that the trial is registered in the fewest number of registers necessary to meet applicable regulations.

Search Portal
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Selective Reporting
This is where the incomplete reporting of trial outcomes associated with statistical significance can result in misleading information.

An individual, company, institution, or organization which takes responsibility for the initiation, management, and/or financing of a clinical trial. (from ICH E6)

An individual who both initiates and conducts, alone or with others, a clinical trial, and under whose immediate direction the investigational product is administered to, dispensed to, or used by a subject (from ICH E6).

Trial Registration Data Set
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Trial Results Database
A trial results database provides the results of completed studies, and should be accompanied by methodological details to place the results in context. The results may or may not have been peer reviewed. A results database may be separate from a trial register. Thus, a trial may be registered in one register and have its results reported in a different results database.

Trial Site
The location(s) where trial-related activities are actually conducted. (from ICH E6)

Unique Trial
A trial is considered a single, unique trial if it is conducted according to a single document (the protocol) that describes the objective(s), design, methodology, statistical considerations, and organization of a trial.

UTN (Universal Trial Number)
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