Table 3.

Population density results for incident myopia.

	Model 1: unadjusted		Model 2: Density only		Model 3: Covariate adjusted
	HR	95% CI	HR	95% CI	HR	95% CI
Assessment occasion (ref age 7)
Age 10	2.17	1.63, 2.92	2.17	1.62, 2.91	2.19	1.63, 2.92
Age 11	1.53	1.1, 2.13	1.52	1.09, 2.13	1.56	1.13, 2.18
Age 12	2.27	1.68, 3.11	2.26	1.65, 3.12	2.35	1.74, 3.2
Age 15	3.53	2.63, 4.8	3.55	2.61, 4.84	3.59	2.67, 4.81
Density			1.12	1.03, 1.24	1.14	1.03, 1.26
Density (squared)			0.99	0.98, 1	0.98	0.97, 1
Male	0.75	0.63, 0.89	0.75	0.63, 0.89	0.8	0.67, 0.96
Age (centred by occasion)	0.91	0.61, 1.34	0.9	0.6, 1.33	0.94	0.62, 1.39
Time outdoors – high (ref low)					0.63	0.48, 0.82
Reading – high (ref low)					1.39	1.16, 1.66
Social class (ref I)
II					0.92	0.72, 1.19
III-NM					1.24	0.95, 1.63
III-M					1.09	0.74, 1.6
IV/V					0.89	0.49, 1.54
Number of myopic parents (ref 0)
1					1.37	1.14, 1.65
2					2.05	1.53, 2.7
KS4 exam point score					1.18	1.07, 1.31
Constant	0.028	0.021, 0.035	0.024	0.017, 0.032	0.026	0.013, 0.054
VPC’s
Neighbourhood VPC	0.004	0.000, 0.020	0.007	0.000, 0.027	0.017	0.001, 0.054
School VPC	0.010	0.000, 0.033	0.013	0.001, 0.039	0.008	0.000, 0.027
Bayesian DIC	4562		4557		4494

HR, Hazard Ratio; VPC, Variance Partition Coefficient; DIC, Deviance Information Criterion.