Table 3.

Mean difference and 95% limits of agreement (LOA) by measurement and corresponding estimated gestational age of ultrasound measurements obtained by two different examiners on 90 fetuses at 18–24 weeks' gestation

		Measurement			Gestational age
Parameter	n	Mean difference (mm (95% CI))	SD (mm)	95% LOA (mm)	Mean difference (weeks (95% CI))	SD (weeks)
BPD	90	− 0.43 (−0.68 to − 0.17)	1.21	− 2.80 to 1.94	− 0.12 (−0.19 to − 0.04)	0.36
HC	90	− 1.63 (−2.63 to − 0.62)	4.80	− 11.0 to 7.77	− 0.12 (−0.20 to − 0.03)	0.42
AC	90	− 0.59 (−1.77 to 0.60)	5.65	− 11.7 to 10.45	− 0.03 (−0.13 to 0.07)	0.50
FL	90	− 0.35 (−0.64 to − 0.07)	1.37	− 3.03 to 2.33	− 0.11 (−0.21 to 0)	0.50

AC, abdominal circumference; BPD, biparietal diameter; FL, femur length; HC, head circumference.