Citation

Averty P, Collet C, Dittmar A, Athènes S, Vernet-Maury E. Aviat. Space Environ. Med. 2004; 75(4): 333-341.

Affiliation

Claude Bernard University, UFR STAPS, CRIS, Villeurbanne Cedex, France.

Copyright

(Copyright © 2004, Aerospace Medical Association)

DOI

unavailable

PMID

15086123

Abstract

BACKGROUND: Mental workload assessment is a recurrent issue in air traffic control (ATC). Studies of ATC have used either objective aspects, i.e., numbers and distribution of aircraft, or subjective factors, such as self-imposed performance and stress levels, with mixed results. This is partly due to the difficulty in bringing together comparable data pertaining to both air traffic, with its ever-changing distribution, and judgement or quickly fluctuating psychophysiological variables. METHODS: We propose a method of mental load estimation devised to take into account both objective traffic variables and the additional load imposed by subjective effects, including the seriousness of conflicts and the time-pressure for their resolution. First, we developed a traffic load index (TLI) to identify time boundaries during which additional load may occur. Then we quantified the additional load according to the air traffic situation. RESULTS: TLI was developed from analysis of 25 h of recordings of radar control sessions involving 25 professional air traffic controllers at a major airport. Results were then compared with a simple objective index (number of aircraft) and subjective workload ratings (NASA-TLX test). The whole population (intersubjects analysis) showed a better correlation between the TLI and the self-rated workload than for the number of aircraft alone. Among the controllers who rated more than one level of workload through the TLX-test, 77.8% showed better correlation between TLI and TLX than between N and TLX (intrasubjects analysis). CONCLUSION: Workload estimation should integrate both objective task variables and subjective evaluations associated with them.

Language: en