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Definitions of Human Subjects and Research

The IRB must review all studies that meet the federal definition of human subjects research, regardless of sponsorship. To determine whether a study is considered human subjects research, the IRB or ORC must first determine:

  1. Does the study meet the federal definition of “research”?
  2. Does the study include “human subjects”?

If the answer is yes to both of these questions, the study is considered “human subjects research” and IRB review is required.

Research Defined

The federal regulations (45 CFR 46.102) define research as “a systematic investigation, including research development, testing and evaluation, designed to develop or contribute to generalizable knowledge.”

Systematic Investigation

A “systematic investigation” is typically a predetermined method for studying a specific topic, answering a specific question(s), testing a specific hypothesis(es) or developing theory. Examples of systematic investigations include:

  • surveys and questionnaires
  • interviews and focus groups
  • observational studies
  • analysis of existing data or biological specimens
  • evaluations of social or educational programs
  • medical chart review studies
  • group comparison studies
  • interventional research

Gray Areas

Case Studies

Case studies prepared and disseminated for educational purposes are not systematic investigations and therefore not considered research. If a researcher is unable to prepare the case study report without disclosing information that would make it possible to identify the individual, they must obtain permission from the individual before using the individual’s data.

Student Class Projects

Some student research projects conducted as part of course requirements may also need IRB review if it falls under the federal definition of research.

Pilot Study

A pilot study is a preliminary investigation of the feasibility of a study, usually intended to help the investigator refine data collection procedures and instruments or prepare a better, more precise research design. These pilot studies are not considered to contribute to generalizable knowledge and therefore would not be defined as research and would not require IRB review.

Data collected from a pilot study cannot be used as research data.

Procedures that are not considered to be pilot study and do not need to be reviewed by the IRB include, but may not be limited to, the following:

  • Training programs designed to teach proven methods that will be used during the conduct  of research (i.e., blood drawing training, interview techniques training);
  • Refining data collection procedures or preparation of an instrument, such as a survey. For instance, “How could this survey question be misunderstood?”, or “In what order should survey instruments be distributed?” This type of study development does not contribute to generalizable knowledge, and therefore is not considered research and does not require IRB review.

Human Subjects Defined

The DHHS federal regulations (45 CFR 46.102) define a human subject as “a living individual about whom an investigator (whether professional or student) conducting research obtains (1) data through intervention or interaction with the individual, or (2) identifiable private information.”

The definition of a human subject focuses on what information or material is obtained from people. If you will obtain either data through interaction or intervention or identifiable private information, the research involves human subjects.


An intervention includes both physical procedures by which data are gathered (for example, venipuncture) and manipulations of the subject or the subject’s environment that are performed for research purposes.


Interaction includes communication or interpersonal contact between investigator and subject. Examples include surveys, interviews, observations, physical measurements, specimen collection (blood, DNA), etc.

Projects that focus on information-gathering where questions focus on existing policies, practices or procedures, (e.g., canvassing about inter-library loan policies or rising journal costs), rather than individuals or their opinions about those policies, do not constitute human subjects research.

Identifiable Private Information

Private information includes 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.

Determination Assistance

Assistance is available from in sorting through the regulatory requirements and definitions and project details.

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