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Generalizable studies are those designed to draw general conclusions (i.e., knowledge gained from a study may be applied to populations outside of the specific study population), inform policy, or generalize findings.
Human Subjects

The Code of Federal Regulations defines a human subject as a living individual about whom an investigator conducting research obtains

  • data through intervention or interaction with the individual (including from interviews and surveys) or
  • identifiable private information.

This does not always require that the researcher interact with a person. Such things as obtaining identified or identifiable secondary data or blood or tissue samples or even playing a small part in another person’s research where there are human subjects and where you would be listed as a co-author would constitute human subject research.


Communication or interpersonal contact between an investigator and a subject.


Both physical procedures by which data are gathered (for example, drawing blood) and manipulations of the subject or the subject’s environment that are performed for research purposes.

Minimal Risk

Minimal risk is the probability and magnitude of physical or psychological harm that is normally encountered in the daily lives, or in the routine medical, dental, or psychological examination of healthy persons (45 CFR 46.303(d)).

Private Information

Information about behavior that occurs in a context in which an individual can reasonably expect that no observation or recording is taking place, and information which has been provided for specific purposes by an individual and which the individual can reasonably expect will not be made public (for example, a medical record). Private information must be individually identifiable (i.e., the identity of the subject is or may readily be ascertained by the investigator or associated with the information) in order for obtaining the information to constitute research involving human subjects.

*Although certain categories of activities involving human beings do not fall under the purview of the IRB, it is important to keep in mind that it is always necessary to respect the rights and safety of all participants in an activity. The concept of informed consent can be applied in non-research settings where it is important to assure that participation is voluntary and consent is documented. Privacy rules apply to research and to other activities. Care should be taken to respect confidentiality and privacy rights of all individuals.


Research is defined as a systematic investigation designed to develop or contribute to general knowledge. It can include research development, testing, evaluation and pilot studies. Intent to publish the results of the study is often an indication that it could be considered research. An exercise designed to demonstrate to students how research is done with no expectation of results that would be published or otherwise contribute to general knowledge may not be considered research. If it is not research, the IRB does not need to review it. However, this is sometimes a difficult distinction to make and it is advisable to request an exemption from the IRB if there is any chance that what you propose to do could be considered or could evolve into research.


Systematic can be defined as any activity that involves a prospective research plan which incorporates data collection, either quantitative or qualitative, and data analysis to answer a research question.

Vulnerable Populations

Federal regulations require that special consideration be given to protecting the welfare of particularly vulnerable populations. These groups include minors, pregnant women, prisoners and fetuses. Special protections are also provided for pregnant women. In general, research involving these populations must be minimal risk or must provide some possible direct benefit to the subject.

For more information, visit the Office for Human Research Protections website..

Additionally, the IRB insures that other populations (for example, decision impaired, economically disadvantages, homeless, elderly, drug or other addiction, terminally or seriously ill, HIV positive, non-English speaking, Tufts employees and students) are protected from coercion or undue influences.