Table 2

Vertical and horizontal disc diameter measurements (VDD and HDD)

		Study A		Study B
	Pupil size	Undilated	Dilated	Undilated	Dilated
	Subjects	N=52	N=34	N=45	N=42
VDD differences (observer 1 − observer 2)		Mean (mm)	0.0557	0.0544	0	0.0071
		Range (mm)	−0.3 to 0.4	−0.15 to 0.2	−0.2 to 0.3	−0.4 to 0.35
		95% limit of agreement	0.2404	0.1607	0.2481	0.2297
		F test		p=0.0125		p=0.609
HDD differences (observer 1 − observer 2)		Mean (mm)	0.0096	0.0147	0.0078	0.0417
		Range (mm)	−0.3 to 0.4	−0.1 to 0.2	−0.35 to 0.25	−0.2 to 0.3
		95% limit of agreement	0.2696	0.1732	0.2463	0.2659
		F test		p=0.0063		p=0.62