Table 4.

Correlation analysis for the text- and graphic-based tasks.

Measure		Correlation value	P
Text-based task
	Average response time	−.84	.002
	Average elapsed time per question	−.72	.02
	NASA-TLXa	−.66	.04
Graphic-based task
	Average response time	−.78	.008
	Average elapsed time per question	−.93	<.001
	NASA-TLXa	−.79	.006

^aNational Aeronautics and Space Administration task load index