Knowledge Center

Clinical Trials Knowledge Center – Articles, FAQ & Glossary

 
Clinical Trials Frequently Asked Questions

Clinical Trial Glossary
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Glossary results: R

A method based on chance by which study participants are assigned to a treatment group. Randomization minimizes the differences among groups by equally distributing people with particular characteristics among all the trial arms. The researchers do not know which treatment is better. From what is known at the time, any one of the treatments chosen could be of benefit to the participant.

A study in which participants are randomly (i.e., by chance) assigned to one of two or more treatment arms of a clinical trial. Occasionally placebos are utilized.

The period during which a trial is attempting to identify and enroll participants. Recruitment activities can include advertising and other ways of soliciting interest from possible participants.

Indicates the current stage of a trial, whether it is planned, ongoing or completed. Possible values include:

  • Not yet recruiting: participants are not yet being recruited or enrolled
  • Recruiting: participants are currently being recruited and enrolled
  • Enrolling by invitation: participants are being (or will be) selected from a predetermined population
  • Active, not recruiting: study is ongoing (i.e., patients are being treated or examined), but enrollment has completed
  • Completed: the study has concluded normally; participants are no longer being examined or treated (i.e., last patient's last visit has occurred)
  • Suspended: recruiting or enrolling participants has halted prematurely but potentially will resume
  • Terminated: recruiting or enrolling participants has halted prematurely and will not resume; participants are no longer being examined or treated
  • Withdrawn: study halted prematurely, prior to enrollment of first participant

The risk to individual participants versus the potential benefits. The risk/benefit ratio may differ depending on the condition being treated.


ClinicalTrials.com provides links to other Internet sites for the user's convenience. ClinicalTrials.com is not responsible for the availability or content of these external sites, nor does it endorse, warrant or guarantee the products, services or information described or offered at these sites.

Information included in the Glossary is from Clinicaltrials.gov, which uses content from AIDSinfo, CenterWatch, Inc., ECRI, Eli Lilly and Company, MediStudy.com, Inc. and National Cancer Institute.