Table 1

Individual refraction values for the right eyes categorised according to birth weights and gestational ages

Characteristic		Number	Spherical equivalent (D)			SCA
			Mean	95 % CI		Mean	95% CI
			Mean	LL	UL	Mean	LL	UL
Total	RE	411	0.34	0.28	0.41	0.51–0.33 178	0.38 −0.27 174	0.64–0.40 1
Total	LE	411	0.34	0.27	0.41	0.43–0.17 10	0.30−0.11 2	0.55–0.23 17
Birth weight (g)
<2500	RE	36	0.30	0.03	0.57	0.51–0.43 3	−0.09−0.16 172	1.06–0.74 13
<2500	LE	36	0.30	0.04	0.56	0.38–0.17 12	0.02−0.04 155	0.86–0.38 58
2500–3500	RE	321	0.34	0.27	0.43	0.51–0.32 177	0.35−0.24 172	0.66–0.40 1
2500–3500	LE	321	0.35	0.28	0.42	0.43–0.18 9	0.28−0.11 2	0.59–0.26 19
>3500	RE	54	0.34	0.21	0.49	0.52–0.34 177	0.22−0.18 163	0.84–0.52 11
>3500	LE	54	0.38	0.23	0.52	0.41–0.07 20	0.20−0.02 118	0.70–0.22 80
Gestational age (weeks)
<37	RE	23	0.27	−0.15	0.69	0.60–0.67 3	−0.25−0.30 174	1.34–1.07 11
<37	LE	23	0.13	−0.32	0.58	0.40–0.53 3	−0.45−0.24 173	1.10–0.85 10
37–42	RE	388	0.33	0.27	0.39	0.50–0.31 176	0.38−0.25 172	0.64–0.38 1
37–42	LE	388	0.35	0.29	0.41	0.43–0.15 11	0.30−0.09 2	0.56–0.21 21
>43	–	0

Mean S C A, compound refractive error calculated via Long's equations (S, Spherical power; C, Cylindrical Power; A, Axis)
LE, left eye; LL, lower limits; RE, right eye; UL, upper limits.