older adult human subject Oliver He A human subject classified as adult, which is defined by NIH as an individual 65 years of age or older. For the purposes of the NIH Policy and Guidelines on the Inclusion of Individuals Across the Lifespan as Participants in Research Involving Human Subjects, an older adult is defined as an individual 65 years of age or older. https://nexus.od.nih.gov/all/2018/08/07/human-subjects-and-clinical-trial-glossary-updates/ adult human subject