Fig. 2From: Assessing the accuracy of ultrasound measurements of tracheal diameter: an in vitro experimental studyBland–Altman analysis of the precision electronic Vernier caliper (PEVC) and ultrasound measurements of tracheal outer transverse diameter (A). Internal transverse diameter (B). Anterior tracheal wall thicknesses (C). The solid line indicates the bias (average difference between paired measurements) and the dotted lines indicate limits of agreement (1.96 ± SD)Back to article page