Table 1.

Comparison of the means ± standard deviations of the subjective ratings of task load measured by the NASA-Task Load Index (NASA-TLX) and driving performance measured by the number of engine stops for the three simulated mission scenarios (n = 39). For the NASA-TLX, scores range from 0 to 100, with higher scores meaning a higher degree of task load. The ANOVAs yielded significant effects of the terrain complexity (all p-values < 0.05).

	Mali Scenario Low Complexity	Afghanistan Scenario Medium Complexity	Circuit Scenario High Complexity
NASA-TLX	13.31 ± 13.10	46.05 ± 19.26	35.62 ± 14.73
Engine stops	0.03 ± 0.16	0.41 ± 0.64	0.15 ± 0.37