The present study re-evaluates five funcional tests for measuring fatigue. These include tapping, colour calling, knee reflex, flicker and two-point discrimination tests. Eight faculty staff and technicians of a medical school were tested in the morning of each working day over a period of four years.
A period of accustomization to the tests was observed. In the first 5 to 10 days of testing scores fluctuated widely; thereafter most test scores remained relatively constant for each individual. However the tapping and colour calling tests required up to one and a half years to become reproducible.
Among subjects there were large variations in the result of the knee reflex and two-point discrimination tests, and relatively small variations for the tapping and flicker tests. In all five tests however intra-personal were significantly less than inter-personal variations.
No age-trend was observed among the subjects, whose ages ranged only from 20 to 40 years.
The female subjects performed the colour calling test faster than the males.
No seasonal pattern was observed. The only weekly pattern was a significantly greater coefficient of variation of the flicker test scores for Thursday and Friday. The menstrual cycle did not appear to affect any of the fatigue test performances.
For individuals accustomed to these tests difference between pre- and post-stress performance may be a reproducible measure of fatigue.
