Table 1.

Repeated measures analysis of change in accuracy from volunteer’s baseline for each time point.

Time point	Event	Accuracy, mean change from baseline (95% CI)	P value
2	30 minutes after Trendelenburg positioning	−0.04 (−0.072 to 0.001)	.06
3	60 minutes after Trendelenburg positioning	-0.01 (−0.05 to 0.03)	.66
4	90 minutes after Trendelenburg positioning	0.01 (−0.03 to 0.05)	.67
5	120 minutes after Trendelenburg positioning	0.02 (−0.02 to 0.05)	.44
6	150 minutes after Trendelenburg positioning	0.002 (−0.35 to 0.04)	.91
7	Supine (after 180 minutes in the Trendelenburg position)	0.02 (−0.01 to 0.06)	.20
8	30 minutes after supine positioning	0.01 (−0.03 to 0.04)	.82
9	Sitting up (60 minutes after supine positioning)	0.02 (−0.02, 0.06)	.29