Understanding Clinical Trial Terminology

Understanding Clinical Trial Terminology

Whether you are interested in possibly participating in a clinical trial or you are interested in staying informed about new treatments to manage a condition, it is important to understand how clinical trials work and their terminology.

The US Food and Drug Administration (FDA) website maintains a handy glossary of Clinical Trial terminology. Here are the main common terms. The term clinical endpoint refers to the clinical outcome of a specific parameter that is being measured by a clinical trial. It relates to the planned objective of the study.

Randomized controlled trials and community trials are the two major types of planned experimental studies. The difference is that the randomized controlled trial analyzes the individual, and the community trial analyzes the group of people.

When preventive therapies are tested, the participants are healthy in preventive measurement (primary prevention). On the other hand, when therapeutic measurements (secondary or tertiary prevention) are underway, the participants have a disease or condition being tested for improvement and safety.

A randomized controlled trial is the strongest study which uses chance in assigning patients to treatments. The purpose of a randomized controlled trial is to ensure no preferential assignments to avoid bias.

The term “control” refers to a person on a substitute placebo or a reference treatment who is not exposed to the test treatment under study. It means the placebo has no known compound activity that would affect the outcome, and it brings a psychosomatic stress-relieving effect of study participation. A placebo must be used to evaluate if improvement in the treated group is due to the drug effect instead of the act of being treated.

Parties of the clinical trial are kept “blind” meaning they are kept unaware of the treatment assignment in the effort to remove judgement. There are three types of blinding, also called masking. A single blind study is when only the patient is blind. A double blind occurs when the patient and the investigator are blind. Lastly a triple blind is when the patient, investigator and data clean-up people are all blind (with the exception of the statistician being partially blinded due to knowing which patients are in the same treatment group. Randomization with blinding avoids reporting bias and all treatment groups are treated the same.

According to the National Institutes of Health, randomized double blind placebo control (RDBPC) studies are considered the “gold standard” of epidemiologic studies. The investigator selects exposure of interest, for example a therapeutic regimen or preventive measure, and subjects are randomly assigned to the exposure and the control (placebo), then they are followed by assessing the outcome compared between the two groups.


About The Author

Kendra Evans

Kendra Evans founded Inflammation Guide in April 2020. Our goal is keeping our readers informed to help them live an empowered and full life while they manage inflammation. Inflammation Guide provides a central location for breaking news and updates on prescriptions, treatments, supplements and alternative wellness solutions to give options to people living with at least one inflammatory condition.

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