A core principe in the Belmont Report that stipulates that researchers should justly distribute the burdens and benefits of the research studey: "(1) to each person an equal share, (2) to each person according to individual need, (3) to each person according to individual effort, (4) to each person according to societal contribution, and (5) to each person according to merit." A key concern when applying this principle is the selection of subjects, that is, the fair recruitment and selection of research subjects (source: The Belmont Report.