Table 1

Relations between psychometric tests and colour vision

Dependent variable	Independent variables	Regression coefficient	95% CI	p value
CI, confidence interval.
*Benton visual retention test error score, Trail making A, and Trailing making B were log transformed before analysis.
†Taking antilogs, regression coefficient is 2.25, 95% CI 1.39 to 3.63.
‡Taking antilogs, regression coefficient is 1.50, 95% CI 1.11 to 2.05.
§Taking antilogs, regression coefficient is 1.47, 95% CI 1.06 to 2.05.
Benton score	CCI	−1.97	−3.21 to 0.72	0.002
	IQ	0.05	0.02 to 0.08	0.002
	Smoking	−0.40	−1.08 to 0.08	0.249
	Alcohol	0.01	−0.02 to 0.03	0.673
	Constant	4.46	0.51 to 8.41	0.027
Benton error score*	CCI†	0.81	0.33 to 1.29	0.001
	IQ	−0.02	−0.04 to 0.01	<0.001
	Smoking	0.12	−0.14 to 0.39	0.359
	Alcohol	−0.004	−0.01 to 0.01	0.429
	Constant	2.80	1.26 to 4.33	0.001
Trail A* (seconds)	CCI‡	0.41	0.10 to 0.72	0.010
	Age	0.01	0.01 to 0.02	0.001
	Smoking	−0.01	−0.17 to 0.15	0.913
	Alcohol	0.003	−0.003 to 0.01	0.357
	Constant	2.30	1.84 to 2.75	<0.001
Trail B* (seconds)	CCI§	0.39	0.06 to 0.72	0.023
	Age	0.02	0.01 to 0.03	<0.001
	Smoking	0.09	−0.08 to 0.26	0.295
	Alcohol	0.003	−0.004 to 0.01	0.423
	Constant	2.78	2.29 to 3.28	<0.001