title: Fuzzy-TLX: using fuzzy integrals for evaluating human mental workload with NASA-Task Load indeX in laboratory and field studies.
abstract: The aim of this study was to assess mental workload in which various load sources must be integrated to derive reliable workload estimates. We report a new algorithm for computing weights from qualitative fuzzy integrals and apply it to the National Aeronautics and Space Administration -Task Load indeX (NASA-TLX) subscales in order to replace the standard pair-wise weighting technique (PWT). In this paper, two empirical studies were reported: (1) In a laboratory experiment, age- and task-related variables were investigated in 53 male volunteers and (2) In a field study, task- and job-related variables were studied on aircrews during 48 commercial flights. The results found in this study were as follows: (i) in the experimental setting, fuzzy estimates were highly correlated with classical (using PWT) estimates; (ii) in real work conditions, replacing PWT by automated fuzzy treatments simplified the NASA-TLX completion; (iii) the algorithm for computing fuzzy estimates provides a new classification procedure sensitive to various variables of work environments and (iv) subjective and objective measures can be used for the fuzzy aggregation of NASA-TLX subscales.
  NASA-TLX, a classical tool for mental workload assessment, is based on a weighted sum of ratings from six subscales. A new algorithm, which impacts on input data collection and computes weights and indexes from qualitative fuzzy integrals, is evaluated through laboratory and field studies. Pros and cons are discussed.
authors.affiliation: Occupational Physiology Laboratory, Institut National de Recherche et de Sécurité, 1 rue du Morvan, CS 60027, F-54519, Vandœuvre, France. marc.mouze-amady@inrs.fr
authors.forename: Marc
authors.initials: M
authors.lastname: Mouzé-Amady
authors.forename: Eric
authors.initials: E
authors.lastname: Raufaste
authors.forename: Henri
authors.initials: H
authors.lastname: Prade
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Meyer
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000401:Aircraft; D000465:Algorithms; D006339:Heart Rate; D006801:Humans; D008297:Male; D008606:Mental Processes / Q000502:physiology; D008875:Middle Aged; D011594:Psychometrics; D057190:Stroop Test; D013647:Task Performance and Analysis; D016526:Workload / Q000523:psychology*