Human Subject Clinical Trials

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The "Human Subjects and Clinical Trials Information" section is required if you are working with human subjects. However, making that determination involves several steps and can be complex.

  • Your research may fall under the umbrella of human subjects even if you aren't working on humans directly.
  • For example, some basic research on samples would be considered human subjects, while research taking a different approach would not.
  • This is a complicated topic with many rules and regulations, so tread carefully, and seek institutional support from your grants office, institutional review board (IRB), and program officer. 
  • The information, tools, and resources below may aid you as you determine whether these policies apply to your work. 

Information on NIH-defined human subjects and clinical trials is included in the PHS Human Subjects and Clinical Trials Information form of the NIH application instructions.  The steps outlined below may be helpful as you navigate through the process of determining whether you are conducting Human Subjects Research and whether that might also be considered as an NIH-defined Clinical Trial.

Step 1: Determine if you are conducting Human Subjects Research

To determine if NIH will consider your study human subjects research, first review SF 424 Form Instructions. The NIH also provides a helpful decision engine to walk you through the steps to inform whether your research may fall under the NIH human subjects designation and if any exemptions from some aspects of the policy may apply.

Step 2: Determine if your proposed study would be an NIH-defined Clinical Trial

The current NIH definition of a clinical trial is broad and is best addressed in a stepwise fashion. Note that researchers that may not consider themselves clinical trialists may be conducting work that would fall under the NIH clinical definition and policies, so it is important to follow the steps below. 

NIH Clinical Trial Decision Tool
Use the NIH Clinical Decision Tool to decide if your human subjects research study meets the NIH definition of a clinical trial
  • You may also find these case studies and FAQs helpful in making your determination.  
  • If questions remain, your institutional grants office, IRB, and as always, an NINDS Program Officer are resources to help you come to a final determination.  

Step 3: Determine what Type of NIH-defined Clinical Trial you are Conducting

It is critical to determine if you are conducting an NIH-defined clinical trial, and if so, what type. This is important for two reasons:

  1. Some funding opportunities will accept only a specific subtype clinical trial. If your proposal contains a clinical trial subtype that is not accepted under a given funding opportunity, your application will be withdrawn prior to review and will not be funded.
  2. In some cases, NINDS will support only a specific type of clinical trial on a funding opportunity. If your proposal contains a clinical trial subtype that is not supported by NINDS under a given funding opportunity, your application will not be funded under any circumstance.

Below are definitions for three types of clinical trials. You will need to know what kind of trial you are proposing in your application to ensure you are applying to an eligible NOFO and one where NINDS would support funding your application. 


Traditional Clinical Trials (Exploratory/Feasibility and Efficacy Trials)

Mechanistic Clinical Trials 

Basic Experimental Studies with Humans Required (BESH)

  • BESH studies are are studies that meet both the definition of basic research and the NIH definition of a clinical trial. BESH therefore are subject to NIH clinical trials policies such as registration and results reporting but may have some exemptions (see the “Policy Flexibilities for BESH Funding Opportunities” section of the BESH website.
  • Note that any proposed study that is primarily BESH or mechanistic in nature but that at any point assess whether an outcome causes an improvement in a health-related outcome, would no longer be considered a BESH or mechanistic trial.

Step 4: Ensure you are applying to the appropriate NOFO

Now that you have established if you are conducting a clinical trial, and if so what kind, next ensure that you are applying to an NOFO that accepts or supports that type of clinical trial.

There are three places you should look to determine the clinical trial requirements or guidelines for a given NOFO:

  1. Review the NOFO’s title and “Section II. Award Information” for what types of clinical trials are allowed, if any. NOTE: This is not enough however, always continue to Step 2.
  2. Review the "Related Notices" section for any affiliated Notices that specify what type of trials are allowed. For example, NINDS has a Notice describing what kinds of trials will be accepted under the parent R01 (Clinical Trial Required) NOFO. 
  3. Finally, review the "Purpose" section of the Funding Opportunity or Notice of Special Interest for any NINDS-specific language regarding the type of clinical trials NINDS (described in Step 3 above) will support under the funding opportunity.


It can be challenging in some cases to differentiate between the different types of NIH-defined clinical trials. If you have questions, consult with your institution’s grants office and an NINDS Program Officer for additional guidance PRIOR to submission.


Want to contact NINDS staff?
Please visit our Find Your NINDS Program Officer page to learn how to find and when to contact a Program Officer, when to contact a Grants Management Specialist, and to learn more about Program Officers and Health Program Specialists.