Trunkey and Botney [19] have developed a series of tests, together named the “MicroCog,” designed to detect “impaired competence occurring late in a physician’s career.” The tests measure “reactivity, attention, numeric recall, verbal memory, visiospatial facility, reasoning, and mental calculation” [19]. According to the overall MicroCog scores, at all ages, physicians (not necessarily surgeons) perform better than nonphysicians, but even physicians by age 75 lose 25% of their starting score. The decline is very rapid by age 60.

Commercial airline pilots are not permitted to act as pilot-in-command past a certain age. The maximum age limit to act as pilot in command in Europe and the United States is 65 years. On both continents, pilots under the maximum allowable age are subjected to frequent medical examinations and performance retesting to assure retention of a safe level of skills.

Trunkey and Botney calculated that if surgeons failed a hypothetical medical test at the same rate that US commercial pilots fail their semiannual medical tests, then 39 surgeons per year would lose privileges in the United States attributable solely to medical problems [19]. Admittedly, their calculation is a gross oversimplification, and an argument can be made that they are very high or very low in their estimate, but the fact remains that some surgeons become incompetent as a result of loss of capabilities with aging; there presently is no systematic method to accurately identify such individuals, and surely some must be continuing to practice.