Decision Tool: Does Your Human Subjects Study Meet the NIH Definition of a Clinical Trial?

Scope Note

A research study in which one or more human subjects are prospectively assigned to one or more interventions (which may include placebo or other control) to evaluate the effects of those interventions on health-related biomedical or behavioral outcomes. To learn more, read NIH's Definition of a Clinical Trial.

Answer the following four questions to determine if your study is a clinical trial:

  1. Does the study involve human participants?
  2. Are the participants prospectively assigned to an intervention?
  3. Is the study designed to evaluate the effect of the intervention on the participants?
  4. Is the effect being evaluated a health-related biomedical or behavioral outcome?
If the answers to the 4 questions are yes, your study is considered to meet the NIH definition of a clinical trial, even if:
  • You are studying healthy participants
  • Your study does not have a comparison group (e.g., placebo or control), or has a single arm
  • Your study is only designed to assess the pharmacokinetics, safety, and/or maximum tolerated dose of an investigational drug
  • Your study is utilizing a behavioral intervention, or measuring intent to change behavior
  • Only one aim or sub-aim of your study meets the clinical trial definition
  • Your study is no more than minimal risk
Your study is NOT considered to meet the NIH definition of a clinical trial if:
  • Your study is intended solely to refine measures.
  • Your study solely involves secondary research with biological specimens or health information.

Decision Tool: Does Your Human Subjects Research Study Meet the NIH Definition of a Clinical Trial?

Note for ancillary studies: When answering the following questions, take into account only the work being proposed in the ancillary study, not the work being done in the parent project.


This page last updated on: September 10, 2024
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