Measuring Workload in Collaborative Contexts

Abstract

Objective: In the present study, we explored the state versus trait aspects of measures of task and team workload in a disaster simulation. Background: There is often a need to assess workload in both individual and collaborative settings. Researchers in this field often use the NASA Task Load Index (NASA-TLX) as a global measure of workload by aggregating the NASA-TLX’s component items. Using this practice, one may overlook the distinction between traits and states. Method: Fifteen dyadic teams (11 inexperienced, 4 experienced) completed five sessions of a tsunami disaster simulator. After every session, individuals completed a modified version of the NASA-TLX that included team workload measures. We then examined the workload items by using a between-subjects and within-subjects perspective. Results: Between-subjects and within-subjects correlations among the items indicated the workload items are more independent within subjects (as states) than between subjects (as traits). Correlations between the workload items and simulation performance were also different at the trait and state levels. Conclusion: Workload may behave differently at trait (between-subjects) and state (within-subjects) levels. Application: Researchers interested in workload measurement as a state should take a within-subjects perspective in their analyses.