The Strategy of Functional Age Research

The metatheoretical ideas underlying the Normative Aging Study research on “Functional Age” are discussed. These ideas have been useful in generating research. It is assumed that each person has a given life-span. This span can be measured either from the date of his birth or, alternatively, from the date of his death. Nearness to death implies older functional age. Different people may make different rates of progress toward their death, tracing out a “life-trajectory.” People may have functional ages and life trajectories which differ from one subsystem to another. In the Normative Aging project at present functional ages have been defined for the domains of Blood Chemistry, Anthropology, Personality, Human Abilities, Sociology, and Hearing. Once defined and determined, these functional ages can be related to each other and searches for leading and lagging functional ages can be made.