Research Integrity: Concise

Human subjects protections

Guiding principles

Human subjects research is based on widely accepted basic principles for responsible conduct

Medicine has long followed the principle of 'do no harm': 'I will do no harm or injustice' to patients (Hippocrates n.d.). In research, guidance on avoiding harm and providing proper protection for human subjects is set out in four major codifications of principle. Anyone conducting human subjects research should have a basic understanding of the principles outlined in these codes.

The codification of basic principles

Nuremberg Code
Declaration of Helsinki
Universal Declaration on Bioethics
Belmont Report

The Nuremberg Code was written to define and prevent the atrocities that occurred during the Second World War. Accordingly, it focuses on the importance of protecting individuals (Nuremberg Military Tribunals, 1949).

The Declaration of Helsinki is more detailed than the Nuremberg Code. It includes specific principles for the way research should be designed, conducted, and reviewed (World Medical Association, 1964, 2002).

The United Nations Educational, Scientific and Cultural Organization (UNESCO) Universal Declaration on Bioethics and Human Rights, as its title suggests, focuses on the rights of research subjects (UNESCO, 2005).

The Belmont Report was issued by the US National Commission for the Protection of Human Subjects of Biomedical and Behavioral Research to provide policy guidance on human subjects research. The report consolidated the patchwork of institutional and national policies that had evolved over the decades into one common set of principles (Belmont Principles), used to guide human subjects research in the United States. They are used for guidance by some countries outside the US (The National Commission for the Protection of Human Subjects of Biomedical and Behavioral Research, 1979).

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Widely accepted basic principles


  • Nuremberg Military Tribunals. (1949) 'The Nuremberg Code', in Trials of War Criminals before the Nuremberg Military Tribunals. Washington, DC: U.S. Government Printing Office.
  • The National Commission for the Protection of Human Subjects of Biomedical and Behavioral Research. (1979) 'The Belmont Report: Ethical Principles and Guidelines for the Protection of Human Subjects of Research', in HHS. Available online at [accessed May 18, 2016].
  • The United Nations Educational, Scientific and Cultural Organization. (2005) 'Universal Declaration on Bioethics and Human Rights'. Available online at
    [accessed January 11, 2016].
  • World Medical Association. (1964, 2002) Declaration of Helsinki: Ethical Principles for Medical Research Involving Human Subjects. Helsinki, Finland: World Medical Association.

The relevance of one particular set of principles over the others depends on where you are conducting your research and the type of research you are conducting. There are, however, five basic principles that are widely accepted in all fields of research and in different countries and cultures:

Voluntary informed consent
Minimum risks
Benefits outweigh risks
Fair distribution of risks and benefits
End participation at any time

Participation in research should be based on voluntary informed consent

Subjects should be asked if they want to participate in a way that does not influence their decision. Keep in mind that your professional status or a particular research situation could influence the decisions subjects make.

Risks to individuals should be minimised

If your research poses any risk, look for ways to reduce the risk. Some risks are unavoidable but should be accepted only if there are no other options.

Benefits from the research should outweigh any risks

Overall, benefits should outweigh risks but the distribution of risks and benefits should also be equitable. One subject or groups of subjects should not benefit at the risk of others.

Benefits and risks should be fairly distributed across populations

Individual subjects or groups of subjects should not be put at greater risk or receive greater rewards than the full population that is the focus of the research.

Subjects should be free to end participation at any time

Subjects can have second thoughts about participation in research and therefore should always have an opportunity to end participation. Ending participation may itself pose risks, e.g. stopping treatment in the middle of a treatment regimen, but subjects still should have an option to withdraw.

If you are not living up to these principles, you may not be meeting your responsibilities.