When Does International Research Need Ethics Review in More Than One Country?

When Does Crossing a Border Mean Adding Another Ethics Review?

An international study can involve several countries without making it obvious how many ethics committees need to review it. The principal investigator may work in one country, the funding may come from another, participants may live in a third, and data may eventually be analyzed somewhere else.

Does every country connected to a project require a separate ethics review? Not necessarily. The more useful question is which institutions and jurisdictions are actually responsible for the research, its participants, and the activities taking place within them.

Multiple Reviews Depend on Where Research Responsibilities Arise

How to Determine Which Countries Need Ethics Review

Start With Where Human-Participant Research Actually Happens

The strongest reason for host-country ethics review arises when research activities involving participants occur there. Recruitment, informed consent, interventions, interviews, observations, access to identifiable records, and collection of biological samples can all create local ethical and regulatory responsibilities.

The 2024 World Medical Association Declaration of Helsinki is explicit for collaborative international medical research: the research protocol must be approved by research ethics committees in both the sponsoring and host countries. It also requires the reviewing committee to have sufficient familiarity with local circumstances and context.

CIOMS similarly states that, for externally sponsored health-related research involving humans, ethical review must occur in both the host and sponsoring institution.

These categories can overlap. A multicountry collaboration may have several genuine research partners rather than one sponsor and one host, and different national systems may use different terminology.

The Number of Countries Is Not the Same as the Number of Required Reviews

Suppose researchers in Country A and Country B jointly analyze a completely de-identified dataset that was lawfully collected previously in Country C. The mere appearance of three countries in the project does not establish that three new full ethics reviews are required. Whether the work constitutes human-participant research requiring review, qualifies for an exemption, or falls under another procedure depends on the applicable systems.

Now change the scenario. Researchers in Country A design and sponsor a study, while teams in Countries B and C recruit participants and collect identifiable health information. The case for ethics oversight in each research setting is much stronger because human-participant research is actually being conducted there.

The question is therefore not simply “How many countries are involved?” but “What research responsibilities and participant-facing activities occur in each country, and which bodies have authority over them?”

Externally Sponsored Research Is a Major Trigger

International ethical guidance pays particular attention to research sponsored from outside the country where participants are located. This arrangement can create a risk that ethical decisions are made remotely without adequate understanding of local conditions.

CIOMS Guideline 23 requires review in both the host and sponsoring institution for externally sponsored health-related research. The dual perspective has a substantive purpose. Sponsor-side review can examine responsibilities arising from the sponsoring institution, while host-side review can address local laws, cultural context, recruitment conditions, participant protections, and other circumstances that may not be apparent to a committee abroad.

WHO's own ethics review process illustrates this layered approach. For WHO-supported research involving human participants, the WHO Research Ethics Review Committee requires submission of local ethics approval among the documentation used in its review process.

A Local Research Partner Can Create Institutional Responsibilities

Adding a university, hospital, research center, or other institution in another country may bring that institution's own ethics policies into the project. Whether it must conduct its own review depends on what it is doing and how its ethics system defines responsibility or engagement in research.

A collaborator who merely advises on terminology is not necessarily equivalent to an institution recruiting participants, obtaining consent, conducting interventions, or accessing identifiable data. Institutional involvement needs to be assessed rather than inferred from a person's name on the research team.

Multisite Research Does Not Always Require Repeating the Same Review

Multiple institutions can sometimes rely on a single ethics committee or use another coordinated arrangement. For example, the U.S. Office for Human Research Protections recognizes documented arrangements under which an institution relies on an external institutional review board for research covered by a Federalwide Assurance. Such reliance must be formally documented rather than casually assumed.

Other jurisdictions may use national committees, centralized review, mutual recognition, lead committees, or different mechanisms. These systems can reduce unnecessary duplication while preserving local responsibilities.

International Medical Guidance Should Not Be Generalized Mechanically to Every Discipline

The Declaration of Helsinki and CIOMS provide particularly influential guidance for medical and health-related research. Their requirements offer useful ethical principles, but a researcher conducting education, sociology, anthropology, economics, humanities, or other research should still verify the rules that actually govern that work.

Some countries or institutions review a broad range of human-participant research. Others distinguish among biomedical research, clinical research, social and behavioral research, secondary data analysis, and activities that fall outside formal ethics-review requirements.

That is why an ethics approval obtained in one country should not simply be assumed to apply elsewhere.

Remote Research Can Still Be International Research

You do not necessarily avoid cross-border ethics questions by staying physically in your home country. A researcher can recruit participants abroad through social media, conduct interviews by video call, distribute an online survey internationally, or remotely access identifiable data held by a foreign institution.

Whether those activities trigger additional ethics review depends on the applicable jurisdictions and institutional policies. Physical travel is therefore a poor proxy for determining where ethical responsibilities arise.

Data Analysis Alone Requires a More Careful Assessment

International collaboration often separates data collection from analysis. A statistician in another country may receive coded or de-identified data without interacting with participants, while the primary study team retains the identifying information.

That does not automatically mean that the statistician's country requires another full ethics review. The status of the activity may depend on identifiability, access, institutional involvement, applicable privacy or data-protection law, and how the relevant ethics system defines human-participant research. Ask the responsible institution for a determination rather than treating either “international” or “de-identified” as a universal answer.

How a Three-Country Study Can Create Several Review Responsibilities

Common Mistakes About Multicountry Ethics Review

Map the Research Before Counting the Ethics Committees

For a multicountry project, create an ethics map before data collection begins. List every country and institution involved, then identify exactly what happens at each location. This is much more informative than starting with a desired number of approvals.

Do this early. Discovering after recruitment begins that a host institution expected prior approval can create more than an administrative inconvenience. It may affect whether research activities were properly authorized and whether data already collected can legitimately be used.

Determine Whether Your International Study Needs Multiple Reviews

Questions About Ethics Review for Multicountry Research

Count Responsibilities, Not Just Countries

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