What Is Broad Consent, and How Broad Can Consent Really Be?

How Can Participants Consent When the Future Studies Are Not Yet Known?

Researchers who build biobanks, longitudinal datasets, repositories, and other research resources face a practical problem. The future scientific value of stored data or biospecimens often lies precisely in questions that have not yet been formulated.

Obtaining study-specific consent for every future project may therefore be difficult or impossible. Broad consent offers another approach: participants can authorize a defined range of future secondary research without being told the details of every study in advance. But “broad” should not be confused with “anything goes.”

Broad Consent Authorizes Categories of Future Research, Not Unlimited Use

Broad Consent Creates Flexibility by Defining a Range Rather Than a Single Study

Study-specific consent and broad consent authorize different things

Traditional study-specific consent asks a person to decide whether to participate in a particular research project whose purpose, procedures, risks, and other relevant features can be described at the time of consent.

Broad consent addresses a different situation. Data or biospecimens may be stored and later reused for secondary research, but investigators cannot yet identify every future question, research team, analytical technique, or project. Instead of seeking permission for one fully specified future study, researchers describe a broader domain of permissible future use.

Broad consent is not simply a vague consent form

Calling consent “broad” does not excuse researchers from explaining what participants are agreeing to. A statement such as “your information may be used for research in the future” may tell participants that reuse is possible, but its adequacy depends on the governing framework and the rest of the consent process.

The U.S. Common Rule provides a particularly concrete regulatory example. Under 45 CFR 46.116(d), broad consent is an alternative consent mechanism for the storage, maintenance, and secondary research use of identifiable private information or identifiable biospecimens. It is optional rather than a universal requirement for secondary research.

Regulatory broad consent contains substantive information

Under the Common Rule, broad consent incorporates several elements associated with informed consent and adds requirements tailored to future secondary use. Among other things, participants must receive a general description of the types of research that may be conducted. That description must provide enough information that a reasonable person would expect the broad consent to permit the research that is ultimately conducted.

The framework also requires information about the identifiable information or biospecimens that might be used, whether sharing might occur, the types of institutions or researchers that might conduct research, and how long materials may be stored and used. Where participants will not receive details of individual future studies, they must be told that they may not be informed about those studies and that some might be studies to which they would have chosen not to consent individually.

Broad does not mean blanket

The distinction is important. Broad consent deliberately leaves some future details unspecified. Blanket consent, by contrast, suggests permission with effectively no meaningful boundary.

A consent process becomes difficult to regard as genuinely informative if researchers reserve every possible future use while giving participants no meaningful indication of the categories of research, access arrangements, relevant risks, or limitations involved. Breadth and absence of information are not the same thing.

The scope of broad consent still has to be respected later

Broad consent does not end the ethical analysis when a new study begins. Someone must still determine whether the proposed secondary research fits the authorization that was originally obtained.

Under the Common Rule exemption at 45 CFR 46.104(d)(8), for example, limited IRB review includes determining whether the proposed secondary research falls within the scope of the broad consent and whether appropriate provisions protect privacy and confidentiality.

This means that how far secondary research can move from the originally authorized purpose remains a live question even when broad consent exists.

Broad consent cannot make unknown future details known

No consent form can accurately describe a study that has not yet been conceived. New technologies may appear. New datasets may become available for linkage. Research questions may shift. Analytical techniques may permit inferences that were technically impossible when the participant originally agreed.

Broad consent therefore works by acknowledging uncertainty rather than pretending to eliminate it. The ethically relevant question becomes whether participants receive enough information about the anticipated range of use, its uncertainties, and its governance to make a meaningful decision despite those unknowns.

This is why whether people can meaningfully consent to research that has not yet been imagined deserves separate consideration from the mechanics of broad consent itself.

Governance becomes more important as future uses become less specific

Study-specific consent places much of the decision in front of the participant: here is the study, and do you agree to it? Broad consent necessarily transfers some future decision-making to governance mechanisms because the participant cannot evaluate every later protocol at the initial consent encounter.

Those mechanisms may include ethics review, repository access committees, data-use agreements, privacy and security controls, restrictions on sharing, oversight of proposed secondary uses, and procedures for handling withdrawals. Their precise form varies by jurisdiction and research setting.

Consent and governance should therefore be understood as complementary rather than interchangeable. Consent provides authorization within a defined range. Governance helps ensure that later uses remain within that range and are otherwise ethically acceptable.

Broad consent is only one possible pathway for secondary research

Researchers sometimes encounter broad consent and assume that every repository must obtain it. That is not the case universally, and it is not even required as the sole route under the Common Rule.

OHRP expressly notes that broad consent is not mandatory. Other pathways may include secondary research using non-identifiable information or biospecimens, applicable exemptions, or an IRB-approved waiver when regulatory criteria are satisfied.

The appropriate route therefore depends on the data, research design, jurisdiction, original authorization, and applicable institutional rules.

Data-protection consent may operate differently from research-ethics broad consent

Researchers should also avoid assuming that a concept defined in one regulatory system automatically satisfies another. Research-ethics consent and consent used as a lawful basis for processing personal information may be governed by different requirements.

For example, Philippine National Privacy Commission guidance emphasizes that consent must be informed and specific to the declared purposes of processing, while also recognizing circumstances in which research processing may rest on another lawful basis or special statutory treatment. The same guidance warns that making information publicly available does not amount to blanket consent for its use for any purpose.

What Broad Consent Might Look Like in Practice

Common Misunderstandings About Broad Consent

Design Broad Consent Around Meaningful Boundaries

If you expect data or biospecimens to support future secondary research, do not begin by asking how to obtain the broadest possible permission. Ask what participants need to understand in order to make a meaningful choice about future use and what governance will keep later research within that authorization.

Before Using Broad Consent for Future Research

Frequently Asked Questions About Broad Consent

Broad Consent Has to Remain Broad Enough for Discovery but Specific Enough for Choice

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