MAP-01-011 HFI Technical Guide - Human Factors Integration ...

MAP-01-011 – HFI Technical Guide (STGP 11)• Although developed for application in the aviation domain, the workloaddimensions are generic, allowing the technique to be applied in anydomain.• Disadvantages• Intrusive to task performance.• Limited applications reported in the literature.• The technique has not been used repeatedly, unlike other subjectiveworkload assessment techniques such as NASA TLX or SWAT.• The workload ratings may correlate highly with performance.• Limited validation evidence is available in the literature. The techniquerequires considerable further testing.A3.6.5Subjective Workload Assessment Technique (SWAT)SWAT is a workload assessment technique that was developed to assess pilotworkload in cockpit environments. SWAT is probably one the most commonlyused of the subjective techniques to measure operator workload and like NASATLX, SWAT is a multidimensional tool that uses three dimensions:1. Time load – the extent to which a task is performed within a time limit andthe extent to which a multiple tasks must be performed concurrently.2. Mental effort load – the associated attentional demands of a task, such asattending to multiple sources of information and performing calculation.3. Stress load – the operator variables such as fatigue, level of training andemotional state.After an initial weighting procedure, participants are asked to rate eachdimension (on a scale of 1 to 3) and from this a workload score is thencalculated.• Advantages• SWAT is a multidimensional approach to workload assessment that isquick, simple and unobtrusive when administered after the event.• The SWAT workload dimensions are generic, so the technique can beapplied to any domain.• The SWAT technique is one of the most widely used and well knowsubjective workload assessment techniques available, and has beensubjected to a number of validation studies.• The Pro-SWAT variation allows the technique to be used predicatively.May 2006 Page A3-48 Issue 4