Functional vs chronologic age.

Chronologic age, by itself, is seldom a reliable index of an individual's ability to perform strenuous physical work. Therefore, age should not be viewed as a bona fide occupational qualification. Instead, each individual should be judged on the basis of his or her functional capabilities. This paper discusses the concept of functional or physiologic age and then considers how functional age can be determined in a specific job-related context. Physiologic age is viewed as a generalized measure of senescence that would be a useful tool for research studies on aging. Functional age could employ many of the marker variables used in the physiologic age (VO2max, strength, etc.) in a task-specific manner. However, since all the variables involve assumptions concerning the rate of decline with age, they may not stand up in a courtroom test. Therefore, the regular use of job-related tests is recommended as an alternative to the use of chronologic or functional age to determine a person's ability to perform on the job.