The probability of harm or injury (physical, psychological, social, or economic) occurring as a result of participation in a research study. Both the probability and magnitude of possible harm may vary from minimal to significant. Federal regulations define only "minimal risk." (See also: Minimal Risk.)  These can include:

• Moderate Risk: The subject will undergo procedures that will increase their risks above those normally encountered in daily life. Equivalent term is "more than minimal risk." These can include, but are not limited to: clinical drug trials, device trials, genetic studies, and risks that include insurability and employability.
• Minimal Risk: The subject will undergo procedures that do not appear to increase the risks above those normally encountered in daily life. These can include but are not limited to studies that involve survey, questionnaire, interview, medical records review, observation of behaviors, drawing a small amount of blood from a healthy individual, etc.
• Exempt: These studies are not usually reviewed by board members, but are reviewed by the chair/analyst. These have been determined to fit certain federal regulations as exempt from IRB review.