The Psychomotor Vigilance Test: Sources of State and Trait Variance

Within the context of pilot and air traffic controller selection tests the Psychomotor Vigilance Test (PVT, Dinges & Powell, 1985) was evaluated for its underlying sources of variance. The PVT is a simple visual reaction time task, which is well established as a measure of alertness during sustained operations. It provides scores for mean reaction times and number of lapses. While the PVT has proven sensitivity for temporary states of fatigue and other stressors in withinsubjects designs, validation studies are lacking to examine it for potential sources of trait variance, which could lead to confounding effects. This paper presents results from a validation study of the PVT with N = 247 air-traffic controller applicants. The PVT was administered in the morning before and in the evening after the selection tests. Lapses and mean reaction times show a different pattern of stability coefficients and inter-correlations with other tests. PVT-lapses appear to be more sensitive to state changes than mean reaction times. However, the change scores of the lapses seem to be confounded with individual personality traits. The PVT reaction time scores show significant correlations to selection tests of psychomotor skills, response orientation and vigilance. Implications for using the PVT as a potential selection test for pilots or air-traffic controllers are discussed.