For Ancillary Studies, Consider NIH Definitions Carefully

Funding News Edition: October 06, 2021
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An ancillary study is an independent research project that uses samples or data from a parent study to extend knowledge in scientific areas beyond the original scope of the parent study. An ancillary study may require additional data or sample collection and it cannot interfere with the primary objectives of the parent study.

Most often, ancillary studies are performed in the context of leveraging research products from large, ongoing clinical trial (CT) networks and studies.

When planning to conduct an ancillary study, you need to assess whether your proposed research qualifies under NIH’s definition of a clinical trial, NIH’s definition of human subjects research, and HHS’s list of exemptions for human subjects research. Those answers will help determine the funding opportunity announcement through which you should apply as well as which forms and sections you need to complete within your grant application.

Your Project May Be a Clinical Trial

Generally, NIH does not consider studies that rely on secondary research with biological specimens or health information to be CTs. When applying to fund such a study, you’ll provide a short description of the source of the data or samples while being clear that the proposed research is not a CT.

However, if the ancillary study adds another prospectively assigned intervention to patients or a subpopulation of patients within the larger clinical trial, it may fulfill the criteria of NIH’s Definition of a Clinical Trial.

Use the decision tool at Does Your Human Subjects Research Study Meet the NIH Definition of a Clinical Trial? to determine whether your project should be labeled as CT research. Answer the four questions considering the secondary study only—not the work being done in the parent project.  

For practical examples, read case studies 42a, 42b, 42c, and NIDCR 1 at NIH Definition of Clinical Trial Case Studies.

Your Project May Be Human Subjects Research

Although not a CT, your project may still qualify as Human Subjects (HS) Research.

Refer to Decision Tool: Am I Doing Human Subjects Research? to determine whether HS are involved. That will help you complete 1. Are Human Subjects Involved? on the G.500 - PHS Human Subjects and Clinical Trials Information form correctly.

TIP: Check "Yes" even if the proposed project is exempt from regulations for the Protection of Human Subjects.

TIP: Refer to NIH’s Exempt Human Subjects Research Infographic and learn of changes to categories of research qualifying for exemptions in HHS’s Revised Common Rule Q&As—Exemptions.

Remember, you can perform HS research without the project also qualifying as CT research. Reference NIH’s application guide for further instruction.

For other helpful resources, read Human Subjects and Clinical Trials Information Form and the updated Annotated Form Sets for NIH Grant Applications—FORMS-F Series.

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