Under federal regulations, human subjects are defined as living individuals from whom data is obtained through:

The definition of human subjects under federal regulations specifically includes living individuals from whom data is obtained through intervention or interaction. This encompasses a wide range of activities, such as administering tests, conducting interviews, and any procedures that might involve participants directly.

Intervention or interaction implies an active engagement with the subjects, whether through physical interventions, such as clinical trials, or behavioral interactions like surveys administered directly to participants. This definition is crucial in ensuring that ethical guidelines are followed in research involving human subjects, protecting their rights and welfare.

While observation, surveys, and analyzing public data may involve collecting information related to individuals, they do not necessarily involve the same level of direct engagement or interaction that defines a human subject under federal regulations. Observing individuals or analyzing data that is already publicly available does not constitute interacting with or intervening in their lives, thus falling outside the specific criteria established for human subject definition.