Registration Data Element Definitions

ClinicalTrials.gov Protocol Registration Data Element Definitions for Int...

https://prsinfo.clinicaltrials.gov/definitions.html

March 7, 2019

This document describes the definitions for protocol registration data elements submitted to
ClinicalTrials.gov for interventional studies (clinical trials) and observational studies. These
definitions are mostly adapted from 42 CFR Part 11.
Data element entries are annotated with symbols to indicate generally what information is required to
be submitted (and under which circumstances). The responsible party must ensure that the
information provided complies with any applicable laws, regulations, or policies. For more
information about various requirements and definitions of regulatory terms under 42 CFR Part 11,
see Support Materials.
Note: The term "clinical study" is used to refer to both interventional and observational studies. The
term "participant" is used to refer to human subjects.
Required
§ Required if Study Start Date is on or after January 18, 2017

[*] Conditionally required

1. Study Identification
Unique Protocol Identification Number
Definition: Any unique identifier assigned to the protocol by the sponsor.
Limit: 30 characters.
Brief Title
Definition: A short title of the clinical study written in language intended for the lay public.
The title should include, where possible, information on the participants, condition being
evaluated, and intervention(s) studied.
Limit: 300 characters.
Acronym [*]
Definition: An acronym or abbreviation used publicly to identify the clinical study, if
any.
Limit: 14 characters.
Official Title §
Definition: The title of the clinical study, corresponding to the title of the protocol.
Limit: 600 characters.

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Secondary IDs [*]
Definition: An identifier(s) (ID), if any, other than the organization's Unique Protocol
Identification Number or the NCT number that is assigned to the clinical study. This includes
any unique clinical study identifiers assigned by other publicly available clinical trial
registries. If the clinical study is funded in whole or in part by a U.S. Federal Government
agency, the complete grant or contract number must be submitted as a Secondary ID.
Limit: 30 characters.
If there is a Secondary ID, then the following information must be provided:
Secondary ID Type [*]
Definition: A description of the type of Secondary ID. Select one.
U.S. National Institutes of Health (NIH) Grant/Contract Award Number: In the
Secondary ID field, include activity code, institute code, and 6-digit serial number.
Other components of the full award number (type code, support year, and suffix)
are optional.
Other Grant/Funding Number: Identifier assigned by a funding organization other
than the U.S. NIH; also required to enter the name of the funding organization.
Registry Identifier: Number assigned by a clinical trial registry (for example, a
registry that is part of the World Health Organization [WHO] Registry Network);
also required to enter the name of the clinical trial registry.
EudraCT Number: Identifier assigned by the European Medicines Agency Clinical
Trials Database (EudraCT).
Other Identifier: Also required to enter a brief description of the identifier (for
example, the name of organization that issued the identifier).
Description [*]
Definition: If a Secondary ID Type of "Other Grant/Funding Number," "Registry
Identifier," or "Other Identifier" is selected, provide the name of the funding
organization, clinical trial registry, or organization that issued the identifier.
Limit: 119 characters.
Study Type
Definition: The nature of the investigation or investigational use for which clinical study
information is being submitted. Select one.
Interventional (clinical trial): Participants are assigned prospectively to an intervention
or interventions according to a protocol to evaluate the effect of the intervention(s) on
biomedical or other health related outcomes.
Observational: Studies in human beings in which biomedical and/or health outcomes are
assessed in pre-defined groups of individuals. Participants in the study may receive
diagnostic, therapeutic, or other interventions, but the investigator does not assign
specific interventions to the study participants. This includes when participants receive
interventions as part of routine medical care, and a researcher studies the effect of the
intervention.
Patient Registry: An observational study that is also considered to be a Patient
Registry. This type of study should only be registered once in the Protocol
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Registration and Results System (PRS), by the sponsor responsible for the primary
data collection and analysis.
Note: The Agency for Healthcare Research and Quality (AHRQ) defines a Patient
Registry as including an organized system that uses observational methods to
collect uniform data (clinical and other) prospectively for a population defined by
a particular disorder/disease, condition (including susceptibility to a disorder), or
exposure (including products, healthcare services, and/or procedures) and that
serves a predetermined scientific, clinical, or policy purpose. Patient registries
may be single purpose or on-going data collection programs that address one or
more questions.
Expanded Access: An investigational drug product (including biological product)
available through expanded access for patients who do not qualify for enrollment in a
clinical trial. Expanded Access includes all expanded access types under section 561 of
the Federal Food, Drug, and Cosmetic Act: (1) for individual patients, including
emergency use; (2) for intermediate-size patient populations; and (3) under a treatment
IND or treatment protocol. (For more information on data requirements for this Study
Type, see Expanded Access Data Element Definitions).

2. Study Status
Record Verification Date
Definition: The date on which the responsible party last verified the clinical study information
in the entire ClinicalTrials.gov record for the clinical study, even if no additional or updated
information is being submitted.
Overall Recruitment Status
Definition: The recruitment status for the clinical study as a whole, based upon the status of the
individual sites. If at least one facility in a multi-site clinical study has an Individual Site Status
of "Recruiting," then the Overall Recruitment Status for the study must be "Recruiting." Select
one.
Not yet recruiting: Participants are not yet being recruited
Recruiting: Participants are currently being recruited, whether or not any participants
have yet been enrolled
Enrolling by invitation: Participants are being (or will be) selected from a predetermined
population
Active, not recruiting: Study is continuing, meaning participants are receiving an
intervention or being examined, but new participants are not currently being recruited or
enrolled
Completed: The study has concluded normally; participants are no longer receiving an
intervention or being examined (that is, last participant’s last visit has occurred)
Suspended: Study halted prematurely but potentially will resume
Terminated: Study halted prematurely and will not resume; participants are no longer
being examined or receiving intervention
Withdrawn: Study halted prematurely, prior to enrollment of first participant
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Why Study Stopped §
Limit: 160 characters.
Definition: A brief explanation of the reason(s) why such clinical study was stopped (for
a clinical study that is "Suspended," "Terminated," or "Withdrawn" prior to its planned
completion as anticipated by the protocol).
Study Start Date §
Definition: The estimated date on which the clinical study will be open for recruitment of
participants, or the actual date on which the first participant was enrolled.
Note: "Enrolled" means a participant's, or their legally authorized representative’s, agreement
to participate in a clinical study following completion of the informed consent process.
Potential participants who are screened for the purpose of determining eligibility for the study,
but do not participate in the study, are not considered enrolled, unless otherwise specified by
the protocol.
Primary Completion Date
Definition: The date that the final participant was examined or received an intervention for the
purposes of final collection of data for the primary outcome, whether the clinical study
concluded according to the pre-specified protocol or was terminated. In the case of clinical
studies with more than one primary outcome measure with different completion dates, this
term refers to the date on which data collection is completed for all of the primary outcomes.
Once the clinical study has reached the primary completion date, the responsible party must
update the Primary Completion Date to reflect the actual primary completion date.
Study Completion Date §
Definition: The date the final participant was examined or received an intervention for
purposes of final collection of data for the primary and secondary outcome measures and
adverse events (for example, last participant’s last visit), whether the clinical study concluded
according to the pre-specified protocol or was terminated.
Once the clinical study has reached the study completion date, the responsible party must
update the Study Completion Date to reflect the actual study completion date.

3. Sponsor/Collaborators

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Responsible Party, by Official Title
Definition: An indication of whether the responsible party is the sponsor, the sponsorinvestigator, or a principal investigator designated by the sponsor to be the responsible party.
Select one.
Sponsor: The entity (for example, corporation or agency) that initiates the study
Principal Investigator: The individual designated as responsible party by the sponsor
(see Note)
Sponsor-Investigator: The individual who both initiates and conducts the study
Note: The sponsor may designate a principal investigator as the responsible party if such
principal investigator meets all of the following requirements: is responsible for conducting the
study; has access to and control over the data from the study; has the right to publish the
results of the study; and has the ability to meet all of the requirements for submitting and
updating clinical study information.
Investigator Information [*]
If the Responsible Party, by Official Title is either "Principal Investigator" or "SponsorInvestigator," the following is required:
Investigator Name: Name of the investigator, including first and last name
Investigator Official Title: The official title of the investigator at the primary
organizational affiliation
Limit: 254 characters.
Investigator Affiliation: Primary organizational affiliation of the individual;
Limit: 160 characters.
Name of the Sponsor
Definition: The name of the entity or the individual who is the sponsor of the clinical study.
Limit: 160 characters.
Note: When a clinical study is conducted under an investigational new drug application (IND)
or investigational device exemption (IDE), the IND or IDE holder is considered the sponsor.
When a clinical study is not conducted under an IND or IDE, the single person or entity who
initiates the study, by preparing and/or planning the study, and who has authority and control
over the study, is considered the sponsor.
Collaborators
Definition: Other organizations (if any) providing support. Support may include funding,
design, implementation, data analysis or reporting. The responsible party is responsible for
confirming all collaborators before listing them.
Limit: 160 characters.

4. Oversight

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Studies a U.S. FDA-regulated Drug Product § (Optional for Observational Studies)
Definition: Indication that a clinical study is studying a drug product (including a biological
product) subject to section 505 of the Federal Food, Drug, and Cosmetic Act or to section 351
of the Public Health Service Act. Select Yes/No.
Studies a U.S. FDA-regulated Device Product § (Optional for Observational Studies)
Definition: Indication that a clinical study is studying a device product subject to section
510(k), 515, or 520(m) of the Federal Food, Drug, and Cosmetic Act. Select Yes/No.
Device Product Not Approved or Cleared by U.S. FDA § (formerly "Delayed
Posting")
Definition: Indication that at least one device product studied in the clinical study has
not been previously approved or cleared by the U.S. Food and Drug Administration
(FDA) for one or more uses. Select one.
Yes: At least one studied FDA-regulated device product has not been previously
approved or cleared by FDA
No: All studied FDA-regulated device products have been previously approved or
cleared by FDA
Note: Full posting of registration information will be delayed if "Yes" is selected and the
study is an applicable clinical trial that is required to be registered under 42 CFR 11.22.
However, the responsible party may authorize NIH to post the information using the
Post Prior to U.S. FDA Approval or Clearance data element.
Post Prior to U.S. FDA Approval or Clearance
Definition: Authorize NIH to post publicly clinical trial registration information
for a clinical study of a device product that has not been previously approved or
cleared (that would otherwise be subject to delayed posting). Select Yes/No.
Pediatric Postmarket Surveillance of a Device Product [*]
Definition: Indication that a clinical study that includes a U.S. FDA-regulated device
product is a pediatric postmarket surveillance of a device product ordered under section
522 of the Federal Food, Drug, and Cosmetic Act. Select Yes/No.
Investigational New Drug Application (IND)/Investigational Device Exemption (IDE)
Information (Optional for Observational Studies)
Definition: Complete the following information regarding an IND or IDE for the clinical study
as defined under U.S. Food and Drug Administration (FDA) regulations in 21 CFR 312.3 or 21
CFR 812, respectively.
U.S. Food and Drug Administration IND or IDE
Definition: Indicate whether the clinical study is being conducted under an IND or IDE
application filed with the FDA. Select one.
(Will not be made public - for administrative purposes only)
Yes: Clinical study is conducted under an IND or IDE filed with the FDA.
No: Clinical study is not conducted under an IND or IDE filed with the FDA.
Includes a clinical study that is “IND exempt” under FDA regulations in 21 CFR

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312.2(b), or is for a nonsignificant risk device subject to FDA-abbreviated IDE
requirements in 21 CFR 812.2(b), or is exempt from the IDE filing requirements
in 21 CFR 812.
If there is an IND or IDE filed with the FDA for the clinical study, the following are
required:
FDA Center [*]
Definition: The name or abbreviation of the FDA Center with which the IND or
IDE is filed. Select one. (Will not be made public - for administrative purposes
only.)
CDER: Center for Drug Evaluation and Research
CBER: Center for Biologics Evaluation and Research
CDRH: Center for Devices and Radiological Health
IND/IDE Number [*]
Definition: IND or IDE number assigned by the FDA Center. (Will not be made
public - for administrative purposes only.)
IND Serial Number [*]
Definition: For an IND, the IND serial number, as defined in 21 CFR 312.23(e), if
any, assigned to the clinical study. (Will not be made public - for administrative
purposes only.)
Availability of Expanded Access [*]
Definition: Whether there is expanded access to the investigational product for
patients who do not qualify for enrollment in a clinical trial. Expanded Access for
investigational drug products (including biological products) includes all
expanded access types under section 561 of the Federal Food, Drug, and Cosmetic
Act: (1) for individual participants, including emergency use; (2) for intermediatesize participant populations; and (3) under a treatment IND or treatment protocol.
Select one.
Yes: Investigational product is available through expanded access
No: Investigational product is not available through expanded access
Unknown: If the responsible party is not the sponsor of the clinical trial and
manufacturer of the investigational product
Expanded Access Record NCT Number [*]
Definition: If expanded access is available, the NCT number of the
expanded access record. If there is no existing expanded access record, the
responsible party who is both the manufacturer of the investigational drug
product (including a biological product) and the sponsor of the ACT is
required to create an expanded access record. (For more information on data
requirements for this Study Type, see Expanded Access Data Element
Definitions).
Product Manufactured in and Exported from the U.S. [*]
Definition: Whether any drug product (including a biological product) or device product

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studied in the clinical study is manufactured in the United States or one of its territories and
exported for study in a clinical study in another country. Required if U.S. FDA-regulated Drug
and/or U.S. FDA-regulated Device is "Yes," U.S. FDA IND or IDE is "No", and Facility
Information does not include at least one U.S. location. Select Yes/No.
Human Subjects Review
Definition: Studies must have approval (or be exempt, as appropriate) from a Human Subjects
Protection Review Board prior to the enrollment of the first participant to be eligible for
registration. A study may be submitted for registration prior to approval by the review board so
long as the study is not yet recruiting participants.
Human Subjects Protection Review Board Status
Definition: Indicate whether a clinical study has been reviewed and approved by at least
one human subjects protection review board or such review is not required per
applicable law (for example, 21 CFR Part 56, 45 CFR Part 46, or other applicable
regulation). Select one.
Request not yet submitted: Review board approval is required but has not yet been
requested
Submitted, pending: Review board approval has been requested but not yet
granted
Submitted, approved: Review board approval has been requested and obtained
Exempt: An exemption in accord with applicable law and regulation has been
granted
Submitted, denied: Review board has denied the approval request
Submission not required: Review board approval is not required because the study
is not subject to laws, regulations, or applicable institutional policies requiring
human subjects review
If the study is not an applicable clinical trial that is required to be registered under 42
CFR Part 11, is not funded in whole or in part by the U.S. Government, and is not
conducted under an IND or IDE, then the following information is required:
Board Approval Number [*]
Definition: Number assigned by the human subjects review board upon approval
of the protocol. May be omitted if status is anything other than approved. (Will not
be made public - for administrative purposes only.)
Board Name [*]
Definition: Full name of the approving human subjects review board. (Will not be
made public - for administrative purposes only.)
Board Affiliation [*]
Definition: Official name of organizational affiliation of the approving human
subjects review board. (Will not be made public - for administrative purposes
only.)
Limit: 255 characters.

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Board Contact [*]
Definition: Contact information for the human subjects review board. (Will not be
made public - for administrative purposes only.)
Phone (or Email required): Phone number
Extension: Phone extension, if needed
Email (or Phone required): Electronic mail address.
Address: Mailing address for the board, including street address, city, State
or province, postal code, and country.
Data Monitoring Committee
Definition: Indicate whether a data monitoring committee has been appointed for this study.
The data monitoring committee (board) is a group of independent scientists who are appointed
to monitor the safety and scientific integrity of a human research intervention, and to make
recommendations to the sponsor regarding the stopping of the trial for efficacy, for harms or
for futility. The composition of the committee is dependent upon the scientific skills and
knowledge required for monitoring the particular study. Select Yes/No.
FDA Regulated Intervention
Definition: Indicate whether this study includes an intervention subject to U.S. Food and
Drug Administration regulation under section 351 of the Public Health Service Act or
any of the following sections of the Federal Food, Drug, and Cosmetic Act: 505, 510(k),
515, 520(m), and 522. Select Yes/No.
Section 801 Clinical Trial
Definition: If this study includes an FDA regulated intervention, indicate whether
this is an applicable clinical trial as defined in U.S. Public Law 110-85, Title VIII,
Section 801. Select Yes/No.

5. Study Description
Brief Summary
Definition: A short description of the clinical study, including a brief statement of the clinical
study's hypothesis, written in language intended for the lay public.
Limit: 5000 characters.
Detailed Description
Definition: Extended description of the protocol, including more technical information (as
compared to the Brief Summary), if desired. Do not include the entire protocol; do not
duplicate information recorded in other data elements, such as Eligibility Criteria or outcome
measures.
Limit: 32,000 characters.
For Patient Registries: Also describe the applicable registry procedures and other quality
factors (for example, third party certification, on-site audit). In particular, summarize any
procedures implemented as part of the patient registry, including, but not limited to the
following:

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Quality assurance plan that addresses data validation and registry procedures, including
any plans for site monitoring and auditing.
Data checks to compare data entered into the registry against predefined rules for range
or consistency with other data fields in the registry.
Source data verification to assess the accuracy, completeness, or representativeness of
registry data by comparing the data to external data sources (for example, medical
records, paper or electronic case report forms, or interactive voice response systems).
Data dictionary that contains detailed descriptions of each variable used by the registry,
including the source of the variable, coding information if used (for example, World
Health Organization Drug Dictionary, MedDRA), and normal ranges if relevant.
Standard Operating Procedures to address registry operations and analysis activities,
such as patient recruitment, data collection, data management, data analysis, reporting
for adverse events, and change management.
Sample size assessment to specify the number of participants or participant years
necessary to demonstrate an effect.
Plan for missing data to address situations where variables are reported as missing,
unavailable, non-reported, uninterpretable, or considered missing because of data
inconsistency or out-of-range results.
Statistical analysis plan describing the analytical principles and statistical techniques to
be employed in order to address the primary and secondary objectives, as specified in
the study protocol or plan.

6. Conditions and Keywords
Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
Definition: The name(s) of the disease(s) or condition(s) studied in the clinical study, or the
focus of the clinical study. Use, if available, appropriate descriptors from NLM's Medical
Subject Headings (MeSH)-controlled vocabulary thesaurus or terms from another vocabulary,
such as the Systematized Nomenclature of Medicine—Clinical Terms (SNOMED CT), that has
been mapped to MeSH within the Unified Medical Language System (UMLS) Metathesaurus.
Keywords
Definition: Words or phrases that best describe the protocol. Keywords help users find studies
in the database. Use NLM's Medical Subject Heading (MeSH)-controlled vocabulary terms
where appropriate. Be as specific and precise as possible. Avoid acronyms and abbreviations.

7. Study Design
Interventional Study Design (For interventional studies only)
Definition: A description of the manner in which the clinical trial will be conducted, including
the following information:
Primary Purpose §
Definition: The main objective of the intervention(s) being evaluated by the clinical trial.
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Select one.
Treatment: One or more interventions are being evaluated for treating a disease,
syndrome, or condition.
Prevention: One or more interventions are being assessed for preventing the
development of a specific disease or health condition.
Diagnostic: One or more interventions are being evaluated for identifying a
disease or health condition.
Supportive Care: One or more interventions are evaluated for maximizing
comfort, minimizing side effects, or mitigating against a decline in the
participant's health or function.
Screening: One or more interventions are assessed or examined for identifying a
condition, or risk factors for a condition, in people who are not yet known to have
the condition or risk factor.
Health Services Research: One or more interventions for evaluating the delivery,
processes, management, organization, or financing of healthcare.
Basic Science: One or more interventions for examining the basic mechanism of
action (for example, physiology or biomechanics of an intervention).
Device Feasibility: An intervention of a device product is being evaluated in a
small clinical trial (generally fewer than 10 participants) to determine the
feasibility of the product; or a clinical trial to test a prototype device for feasibility
and not health outcomes. Such studies are conducted to confirm the design and
operating specifications of a device before beginning a full clinical trial.
Other: None of the other options applies.
Study Phase
Definition: For a clinical trial of a drug product (including a biological product), the
numerical phase of such clinical trial, consistent with terminology in 21 CFR 312.21 and
in 21 CFR 312.85 for phase 4 studies. Select only one.
N/A: Trials without phases (for example, studies of devices or behavioral
interventions).
Early Phase 1 (Formerly listed as "Phase 0"): Exploratory trials, involving very
limited human exposure, with no therapeutic or diagnostic intent (e.g., screening
studies, microdose studies). See FDA guidance on exploratory IND studies for
more information.
Phase 1: Includes initial studies to determine the metabolism and pharmacologic
actions of drugs in humans, the side effects associated with increasing doses, and
to gain early evidence of effectiveness; may include healthy participants and/or
patients.
Phase 1/Phase 2: Trials that are a combination of phases 1 and 2.
Phase 2: Includes controlled clinical studies conducted to evaluate the
effectiveness of the drug for a particular indication or indications in participants
with the disease or condition under study and to determine the common short-term
side effects and risks.
Phase 2/Phase 3: Trials that are a combination of phases 2 and 3.
Phase 3: Includes trials conducted after preliminary evidence suggesting

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effectiveness of the drug has been obtained, and are intended to gather additional
information to evaluate the overall benefit-risk relationship of the drug.
Phase 4: Studies of FDA-approved drugs to delineate additional information
including the drug's risks, benefits, and optimal use.
Interventional Study Model §
Definition: The strategy for assigning interventions to participants.
Single Group: Clinical trials with a single arm
Parallel: Participants are assigned to one of two or more groups in parallel for the
duration of the study
Crossover: Participants receive one of two (or more) alternative interventions
during the initial phase of the study and receive the other intervention during the
second phase of the study
Factorial: Two or more interventions, each alone and in combination, are
evaluated in parallel against a control group
Sequential: Groups of participants are assigned to receive interventions based on
prior milestones being reached in the study, such as in some dose escalation and
adaptive design studies
Model Description
Definition: Provide details about the Interventional Study Model.
Limit: 1000 characters.
Number of Arms §
Definition: The number of arms in the clinical trial. For a trial with multiple periods or
phases that have different numbers of arms, the maximum number of arms during all
periods or phases.
Note: "Arm" means a pre-specified group or subgroup of participant(s) in a clinical trial
assigned to receive specific intervention(s) (or no intervention) according to a protocol.
Masking §
Definition: The party or parties involved in the clinical trial who are prevented from
having knowledge of the interventions assigned to individual participants. Select all that
apply.
Roles, if Masking:
Participant
Care Provider
Investigator
Outcomes Assessor: The individual who evaluates the outcome(s) of
interest
No Masking
Masking Description
Definition: Provide information about other parties who may be masked in the
clinical trial, if any.
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Limit: 1000 characters.
Allocation §
Definition: The method by which participants are assigned to arms in a clinical trial.
N/A (not applicable): For a single-arm trial
Randomized: Participants are assigned to intervention groups by chance
Nonrandomized: Participants are expressly assigned to intervention groups
through a non-random method, such as physician choice
Enrollment §
Definition: The estimated total number of participants to be enrolled (target number) or
the actual total number of participants that are enrolled in the clinical study.
Note: "Enrolled" means a participant’s, or their legally authorized representative’s,
agreement to participate in a clinical study following completion of the informed consent
process. Potential participants who are screened for the purpose of determining
eligibility for a study, but do not participate in the study, are not considered enrolled,
unless otherwise specified by the protocol.
Observational Study Design (For observational studies only)
Observational Study Model
Definition: Primary strategy for participant identification and follow-up. Select one.
Cohort: Group of individuals, initially defined and composed, with common
characteristics (for example, condition, birth year), who are examined or traced
over a given time period.
Case-Control: Group of individuals with specific characteristics (for example,
conditions or exposures) compared to group(s) with different characteristics, but
otherwise similar.
Case-Only: Single group of individuals with specific characteristics.
Case-Crossover: Characteristics of case immediately prior to disease onset
(sometimes called the hazard period) compared to characteristics of same case at a
prior time (that is, control period).
Ecologic or Community Studies: Geographically defined populations, such as
countries or regions within a country, compared on a variety of environmental (for
example, air pollution intensity, hours of sunlight) and/or global measures not
reducible to individual level characteristics (for example, healthcare system, laws
or policies median income, average fat intake, disease rate).
Family-Based: Studies conducted among family members, such as genetic studies
within families or twin studies and studies of family environment.
Other: Explain in Detailed Description.
Time Perspective
Definition: Temporal relationship of observation period to time of participant
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enrollment. Select one.
Retrospective: Look back using observations collected predominantly prior to
subject selection and enrollment
Prospective: Look forward using periodic observations collected predominantly
following subject enrollment
Cross-sectional: Observations or measurements made at a single point in time,
usually at subject enrollment
Other: Explain in Detailed Description
Biospecimen Retention
Definition: Indicate whether samples of material from research participants are retained
in a biorepository. Select one.
None Retained: No samples retained
Samples With DNA: Samples retained, with potential for extraction of DNA from
at least one of the types of samples retained (e.g., frozen tissue, whole blood)
Samples Without DNA: Samples retained, with no potential for DNA extraction
from any retained samples (e.g., fixed tissue, plasma)
Biospecimen Description
Definition: Specify all types of biospecimens to be retained (e.g., whole blood, serum,
white cells, urine, tissue).
Limit: 1000 characters.
Enrollment
Definition: The estimated total number of participants to be enrolled (target number) or
the actual total number of participants that are enrolled in the clinical study.
Note: "Enrolled" means a participant’s, or their legally authorized representative’s,
agreement to participate in a clinical study following completion of the informed consent
process. Potential participants who are screened for the purpose of determining
eligibility for a study, but do not participate in the study, are not considered enrolled,
unless otherwise specified by the protocol.
Target Follow-Up Duration
Definition: For Patient Registries, the anticipated time period over which each
participant is to be followed. Provide a number and select a Unit of Time (years, months,
weeks, days).
Number of Groups/Cohorts
Definition: Number of study groups/cohorts. Enter "1" for a single-group study. Many
observational studies have one group/cohort; case control studies typically have two.

8. Arms, Groups, and Interventions

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Arm Information (For interventional studies only)
Definition: A description of each arm of the clinical trial that indicates its role in the clinical
trial; provides an informative title; and, if necessary, additional descriptive information
(including which interventions are administered in each arm) to differentiate each arm from
other arms in the clinical trial.
Note: "Arm" means a pre-specified group or subgroup of participant(s) in a clinical trial
assigned to receive specific intervention(s) (or no intervention) according to a protocol.
Arm Title
Definition: The short name used to identify the arm.
Limit: 62 characters.
Arm Type
Definition: The role of each arm in the clinical trial.
Experimental
Active Comparator
Placebo Comparator
Sham Comparator
No Intervention
Other
Arm Description [*]
Definition: If needed, additional descriptive information (including which interventions
are administered in each arm) to differentiate each arm from other arms in the clinical
trial.
Limit: 999 characters.

Group/Cohort Information (For observational studies only)
Definition: Specify the predefined participant groups (cohorts) to be studied, corresponding to
Number of Groups specified under Study Design (for single-group studies, the following data
elements are optional). Do not use this section to specify strata (Detailed Description can be
used for that purpose, if desired).
Limit: 62 characters.
Group/Cohort Label
Definition: The short name used to identify the group.
Group/Cohort Description [*]
Definition: Explanation of the nature of the study group (for example, those with a
condition and those without a condition; those with an exposure and those without an
exposure).
Limit: 1000 characters.
Note: The overall study population should be described under Eligibility.

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Interventions
Definition: Specify the intervention(s) associated with each arm or group; at least one
intervention must be specified for interventional studies. For observational studies, specify the
intervention(s)/exposure(s) of interest, if any. If the same intervention is associated with more
than one arm or group, provide the information once and use the Arm or Group/Intervention
Cross-Reference to associate it with more than one arm or group.
Intervention Type
Definition: For each intervention studied in the clinical study, the general type of
intervention. Select one.
Drug: Including placebo
Device: Including sham
Biological/Vaccine
Procedure/Surgery
Radiation
Behavioral: For example, psychotherapy, lifestyle counseling
Genetic: Including gene transfer, stem cell and recombinant DNA
Dietary Supplement: For example, vitamins, minerals
Combination Product: Combining a drug and device, a biological product and
device; a drug and biological product; or a drug, biological product, and device
Diagnostic Test: For example, imaging, in-vitro
Other
Intervention Name(s)
Definition: A brief descriptive name used to refer to the intervention(s) studied in each
arm of the clinical study. A non-proprietary name of the intervention must be used, if
available. If a non-proprietary name is not available, a brief descriptive name or
identifier must be used.
Limit: 200 characters.
Other Intervention Name(s) [*]
Definition: Other current and former name(s) or alias(es), if any, different from the
Intervention Name(s), that the sponsor has used publicly to identify the
intervention(s), including, but not limited to, past or present names such as brand
name(s), or serial numbers.
Limit: 200 characters.
Intervention Description §
Definition: Details that can be made public about the intervention, other than the
Intervention Name(s) and Other Intervention Name(s), sufficient to distinguish the
intervention from other, similar interventions studied in the same or another clinical
study. For example, interventions involving drugs may include dosage form, dosage,
frequency, and duration.
Limit: 1000 characters.
Arm or Group/Interventional Cross-Reference
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Definition: If multiple Arms or Groups have been specified, indicate which Interventions (or
exposures) are in each Arm or Group of the study, using the Cross-Reference check boxes.

9. Outcome Measures
Primary Outcome Measure Information
Definition: A description of each primary outcome measure (or for observational studies,
specific key measurement[s] or observation[s] used to describe patterns of diseases or traits or
associations with exposures, risk factors or treatment).
Note: "Primary outcome measure" means the outcome measure(s) of greatest importance
specified in the protocol, usually the one(s) used in the power calculation. Most clinical studies
have one primary outcome measure, but a clinical study may have more than one.
For each primary outcome measure, include the following information:
Title: Name of the specific primary outcome measure
Limit: 254 characters.
Description: [*] Description of the metric used to characterize the specific primary
outcome measure, if not included in the primary outcome measure title.
Limit: 999 characters.
Time Frame: Time point(s) at which the measurement is assessed for the specific
metric used. The description of the time point(s) of assessment must be specific to the
outcome measure and is generally the specific duration of time over which each
participant is assessed (not the overall duration of the study).
Limit: 254 characters.
Secondary Outcome Measure Information [*]
Definition: A description of each secondary outcome measure (or for observational studies,
specific secondary measurement[s] or observation[s] used to describe patterns of diseases or
traits or associations with exposures, risk factors or treatment).
Note: "Secondary outcome measure" means an outcome measure that is of lesser importance
than a primary outcome measure, but is part of a pre-specified analysis plan for evaluating the
effects of the intervention or interventions under investigation in a clinical study and is not
specified as an exploratory or other measure. A clinical study may have more than one
secondary outcome measure.
For each secondary outcome measure, include the following information:
Title:

Name of the specific secondary outcome measure

Description: [*] Description of the metric used to characterize the specific secondary
outcome measure, if not included in the secondary outcome measure title.
Time Frame: Time point(s) at which the measurement is assessed for the specific
metric used. The description of the time point(s) of assessment must be specific to the

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outcome measure and is generally the specific duration of time over which each
participant is assessed (not the overall duration of the study).

Other Pre-specified Outcome Measures
Definition: Any other measurements, excluding post-hoc measures, that will be used to
evaluate the intervention(s) or, for observational studies, that are a focus of the study.
Title:

Name of the specific other pre-specified outcome measure

Description: [*] Description of the metric used to characterize the specific other prespecified outcome measure, if not included in the other pre-specified outcome measure
title.
Time Frame: Time point(s) at which the measurement is assessed for the specific
metric used. The description of the time point(s) of assessment must be specific to the
outcome measure and is generally the specific duration of time over which each
participant is assessed (not the overall duration of the study).

10. Eligibility
Sex/Gender
Definition: The sex and, if applicable, gender of the participants eligible to participate in the
clinical study.
Sex
Definition: The sex of the participants eligible to participate in the clinical study. Select
one.
Note: "Sex" means a person's classification as male or female based on biological
distinctions.
All: Indicates no limit on eligibility based on the sex of participants
Female: Indicates that only female participants are being studied
Male: Indicates that only male participants are being studied
Gender Based [*]
Definition: If applicable, indicate whether participant eligibility is based on
gender. Select one.
Note: "Gender" means a person's self-representation of gender identity.
Yes: Eligibility is based on gender
No: Eligibility is not based on gender
Gender Eligibility Description
Definition: If eligibility is based on gender, provide descriptive information
about Gender criteria.
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Limit: 1000 characters.
Age Limits
Definition: The minimum and maximum age of potential participants eligible for the clinical
study, provided in relevant units of time.
Minimum Age
Definition: The numerical value, if any, for the minimum age a potential participant
must meet to be eligible for the clinical study.
Unit of Time
Select one.
Years
Months
Weeks
Days
Hours
Minutes
N/A (No limit)
Maximum Age
Definition: The numerical value, if any, for the maximum age a potential participant can
be to be eligible for the clinical study.
Unit of Time
Select one.
Years
Months
Weeks
Days
Hours
Minutes
N/A (No limit)
Accepts Healthy Volunteers § (Optional for Observational Studies)
Definition: Indication that participants who do not have a disease or condition, or related
conditions or symptoms, under study in the clinical study are permitted to participate in the
clinical study. Select Yes/No.
Eligibility Criteria
Definition: A limited list of criteria for selection of participants in the clinical study, provided
in terms of inclusion and exclusion criteria and suitable for assisting potential participants in
identifying clinical studies of interest. Use a bulleted list for each criterion below the headers
"Inclusion Criteria" and "Exclusion Criteria".

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Limit: 15,000 characters.
Study Population Description (For observational studies only)
Definition: A description of the population from which the groups or cohorts will be selected
(for example, primary care clinic, community sample, residents of a certain town).
Limit: 1000 characters.
Sampling Method (For observational studies only)
Definition: Indicate the method used for the sampling approach and explain in the Detailed
Description. Select one.
Probability Sample: Exclusively random process to guarantee that each participant or
population has specified chance of selection, such as simple random sampling,
systematic sampling, stratified random sampling, cluster sampling, and consecutive
participant sampling
Non-Probability Sample: Any of a variety of other sampling processes, such as
convenience sampling or invitation to volunteer

11. Contacts, Locations, and Investigator Information
Central Contact Person (or Facility Contact required)
Definition: The name or title, toll-free telephone number and email address of a person to
whom questions concerning enrollment at any location of the study can be addressed. Include
the following information:
First Name
Middle Initial
Last Name or Official Title
Degree
Phone: Toll free phone number of the Central Contact Person. Use the format
800-555-5555 within the United States and Canada. If outside the United States and
Canada, provide the full phone number, including the country code.
Ext: phone extension, if needed
Email:

electronic mail address of the central contact person

Central Contact Backup
Definition: Person to contact if Central Contact is not available. Include the following
information:
First Name
Middle Initial

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Last Name or Official Title
Degree
Phone: Toll free phone number of the Central Contact Backup. Use the format
800-555-5555 within the United States and Canada. If outside the United States and
Canada, provide the full phone number, including the country code.
Ext: Phone extension, if needed
Email: Electronic mail address of the contact person
Overall Study Officials
Definition: Person(s) responsible for the overall scientific leadership of the protocol, including
study principal investigator. Include the following information:
First Name
Middle Initial
Last Name
Degree
Organizational Affiliation: Full name of the official's organization. If none, specify
Unaffiliated.
Limit: 255 characters.
Official's Role: Position or function of the official. Select one
Study Chair
Study Director
Study Principal Investigator
Facility Information
Definition: For each participating facility in a clinical study, the following information:
Facility Name: § Full name of the organization where the clinical study is being
conducted.
Limit: 254 characters.
City
State/Province:
States)
ZIP/Postal Code:
States)

Required for U.S. locations (including territories of the United
§ Required for U.S. locations (including territories of the United

Country
Individual Site Status
Definition: The recruitment status of each participating facility in a clinical study.
Not yet recruiting: Participants are not yet being recruited
Recruiting: Participants are currently being recruited, whether or not any participants
have yet been enrolled
Enrolling by invitation: Participants are being, or will be selected from a predetermined
population
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Active, not recruiting: Study is continuing, meaning participants are receiving an
intervention or being examined, but new participants are not currently being recruited or
enrolled
Completed: The study has concluded normally; participants are no longer receiving an
intervention or being examined (that is, the last participant's last visit has occurred)
Suspended: Study halted prematurely but potentially will resume
Terminated: Study halted prematurely and will not resume; participants are no longer
being examined or receiving intervention
Withdrawn: Study halted prematurely, prior to enrollment of first participant

Facility Contact (or Central Contact required)
Definition: For each facility participating in a clinical study, including the name or title,
telephone number, and email address of a person to whom questions concerning the study and
enrollment at that site can be addressed. Include the following information:
First Name
Middle Initial
Last Name or Official Title
Degree
Phone:

Office phone of the Facility Contact.

Ext: phone extension, if needed
Email:

Electronic mail address of the facility contact person

Facility Contact Backup
Definition: Person to contact if Facility Contact is not available (that is, a second contact
person).
Investigators (at the facility location). Include the following information:
First Name
Middle Initial
Last Name
Degree
Role:
Site Principal Investigator
Site Sub-Investigator
Contact information character limits:
First Name: 62 characters
Last Name: 62 characters
Degree: 30 characters
Phone: 30 characters

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Phone Ext: 14 characters
Email: 254 characters

12. IPD Sharing Statement
Plan to Share IPD
Definition: Indicate whether there is a plan to make individual participant data (IPD) collected
in this study, including data dictionaries, available to other researchers (typically after the end
of the study). Select one.
Yes: There is a plan to make IPD and related data dictionaries available.
No: There is not a plan to make IPD available.
Undecided: It is not yet known if there will be a plan to make IPD available.
IPD Sharing Plan Description
Definition: If Plan to Share IPD is "Yes," briefly describe what specific individual
participant data sets are to be shared (for example, all collected IPD, all IPD that
underlie results in a publication). If the Plan to Share IPD is "No" or "Undecided," an
explanation may be provided for why IPD will not be shared or why it is not yet decided.
Limit: 1000 characters.
If Plan to Share IPD is "Yes," provide the following information.
IPD Sharing Supporting Information Type
Definition: The type(s) of supporting information that will be shared, in addition to the
individual participant data set and data dictionaries for the IPD itself. Select all that
apply.
Study Protocol
Statistical Analysis Plan (SAP)
Informed Consent Form (ICF)
Clinical Study Report (CSR)
Analytic Code
IPD Sharing Time Frame
Definition: A description of when the IPD and any additional supporting information
will become available and for how long, including the start and end dates or period of
availability. This may be provided as an absolute date (for example, starting in January
2025) or as a date relative to the time when summary data are published or otherwise
made available (for example, starting 6 months after publication).
Limit: 1000 characters.
IPD Sharing Access Criteria
Definition: Describe by what access criteria IPD and any additional supporting
information will be shared, including with whom, for what types of analyses, and by
what mechanism. Information about who will review requests and criteria for reviewing
requests may also be provided.
Limit: 1000 characters.

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IPD Sharing URL
Definition: The web address, if any, used to find additional information about the plan to
share IPD.
Limit: 3999 characters.

13. References
Citations
Definition: Citations to publications related to the protocol: background and/or results. Provide
either the PubMed Unique Identifier (PMID) of an article or enter the full bibliographic
citation.
PubMed Identifier
Definition: PMID for the citation in MEDLINE
Citation
Definition: A bibliographic reference in NLM's MEDLINE format
Limit: 2000 characters.
Results Reference
Definition: Indicate if the reference provided reports on results from this clinical study.
Select Yes/No.
Links
Definition: A web site directly relevant to the protocol may be entered, if desired. Do not
include sites whose primary goal is to advertise or sell commercial products or services. Links
to educational, research, government, and other non-profit web pages are acceptable. All
submitted links are subject to review by ClinicalTrials.gov.
URL
Definition: Complete URL, including http:// or https://
Limit: 3999 characters.
Description
Definition: Title or brief description of the linked page.
Limit: 254 characters.
Available IPD and Supporting Information
Definition: The individual participant data (IPD) sets and supporting information that are being
shared for the study. Provide the following information for each:
Available IPD/Information Type
Definition: The type of data set or supporting information being shared.
Individual Participant Data Set
Study Protocol
Statistical Analysis Plan

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Informed Consent Form
Clinical Study Report
Analytic Code
Other (specify)
Available IPD/Information URL
Definition: The web address used to request or access the data set or supporting
information.
Limit: 3999 characters.
Available IPD/Information Identifier
Definition: The unique identifier used by a data repository for the data set or supporting
information.
Limit: 30 characters.
Available IPD/Information Comments
Definition: Additional information including the name of the data repository or other
location where the data set or supporting information is available. Provide any additional
explanations about the data set or supporting information and instructions for obtaining
access, particularly if a URL is not provided.
Limit: 1000 characters.

A.1 Document Upload Information
For details on uploading study documents (study protocol, statistical analysis plan, and/or
informed consent form), see the Document Upload Information in the Results Data Element
Definitions.

A.2 Responsible Party Contact Information §
(Provided as part of User Information or Organization Information in a PRS Account)
Definition: Administrative information to identify and enable communication with the
responsible party by telephone, email, and regular mail or delivery service. Responsible Party
Contact Information is for the individual who is the responsible party or of a designated
employee of the organization that is the responsible party. (Will not be made public - for
administrative purposes only.)
Note: "Responsible party" means with respect to a clinical study, the sponsor of the clinical
study, as defined in 21 CFR 50.3; or the principal investigator of such clinical study if so
designated by a sponsor, grantee, contractor, or awardee, so long as the principal investigator is

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responsible for conducting the study, has access to and control over the data from the clinical
study, has the right to publish the results of the study, and has the ability to meet all of the
requirements for the submission of clinical study information. For a pediatric postmarket
surveillance of a device product that is not a clinical trial, the responsible party is the entity
who FDA orders to conduct the pediatric postmarket surveillance of the device product.
Name of Individual
Official Title
Physical Address
Name of Organizational Affiliation
Street Address
City
State/Province
ZIP/Postal Code
Country
Mailing Address

(If different from Physical Address)

Name of Organizational Affiliation
Street Address
City
State/Province
ZIP/Postal Code
Country
Phone: Use the format 800-555-5555 within the United States and Canada.
Otherwise, provide the full number, including the country code.
Ext: phone extension, if needed
Email:

Electronic mail address

History of Changes
January 18, 2017: Document updated with data element changes per the FDAAA 801 final
rule (42 CFR Part 11).
February 07, 2017: Formatting and typographical errors were corrected.
April 18, 2017: Added clarification that "(clinical trial)" has the same meaning as
"Interventional" in Study Type and added definitions for "Yes" and "No" in U.S. Food and
Drug Administration IND or IDE. Product Manufactured in and Exported from the U.S. and
Outcome Measure Description definitions modified to describe when the information is
required. Modified Cross-Reference element to address observational studies. Minor

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formatting changes.
June 29, 2017: Updated data elements related to Plan to Share IPD and moved to IPD Sharing
Statement module. Added Document Upload Information reference (to Results Data Elements
Definitions) as Appendix 1 (A.1.). Labeled Responsible Party Contact Information as
Appendix 2 (A.2.). Brief Title, Study Phase - Early Phase 1, Collaborators, and Primary
Purpose - Device Feasibility definitions updated with additional information to clarify
meaning.
June 27, 2018: Typographical errors were corrected.
March 7, 2019: Updated Patient Registry definition to link to the most recent edition of the
Registries for Evaluating Patient Outcomes: A User's Guide.

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