Table 3.

Values of Constants a_i and b_i

Clinical Parameters	Constants’ Values
	ai	bi
UDVA	0.71	0.042
UIRA	0.43	0.040
UICPS	0.39	0.041
UNRA	0.51	0.038
UNCPS	0.49	0.039
Glare	0.28	0.047
Shadows	0.29	0.048
CS	0.40	0.051
SFP-NV	0.81	0.042
SFP-DV	0.82	0.044
SFP (total)	0.90	0.043

Abbreviations: UDVA, uncorrected distance visual acuity; UIRA, uncorrected intermediate reading acuity (at 60 cm); UICPS, uncorrected intermediate critical print size (at 60 cm); UNRA, uncorrected near reading acuity (at 40 cm); UNCPS, uncorrected near critical print size (at 40 cm); CS, contrast sensitivity; SFP-NV, spectacle-free patients for near vision activities; SFP-DV, spectacle-free patients for distance vision activities; SFP (total), spectacle-free patients for all distances.