Table 5.

Regression analysis of factors that explain the progression of myopia ^†.

	(1)	(2)	(3)
	All Children	Primary School	Secondary School
Length (years)	0.02 *	0.02 **	0.01
	(1.76)	(1.81)	(0.74)
Boy	0.03	0.04 *	0.05
	(1.22)	(1.75)	(0.67)
Growth in Height	0.01 **	0.03 ***	−0.002
(cm)	(1.92)	(3.71)	(−0.16)
BMI	0.02 **	0.02 **	0.003
	(2.28)	(2.00)	(0.17)
Weight (kg)	−0.01 ***	−0.01 **	−0.004
	(−3.37)	(−2.30)	(−0.91)
Space	−0.002	0.01	−0.01
	(−0.22)	(0.60)	(−0.49)
Income ‡	0.03	0.03	−0.001
	(0.76)	(0.94)	(−0.02)
Mydratic Use	−0.03	−0.03	−0.03
	(−1.00)	(−0.66)	(−0.47)
Private School	−0.03	−0.04	0.01
	(−0.85)	(−1.14)	(0.11)
Eye Care	−0.001	−0.0001	−0.001
Knowledge	(−0.32)	(−0.07)	(−0.58)
Genetics	0.03 *	0.06 **	−0.01
	(1.66)	(1.99)	(−0.22)
School Performance	−0.01	−0.01	0.003
	(−0.87)	(−1.26)	(0.17)
Food Supplements
Vitamin	−0.01	−0.03	0.05
	(−0.12)	(−0.70)	(0.40)
Fish oil	0.01	0.04	−0.02
	(0.28)	(0.73)	(−0.28)
Activity Hours
Cram School	0.01 *	0.01	0.02
	(1.62)	(1.47)	(1.37)
Electronics	0.04 **	0.01	0.05 *
	(2.26)	(0.45)	(1.80)
TV	−0.01	0.02	−0.02
	(−0.42)	(1.10)	(−0.88)
Study	0.01	−0.02	0.01
	(0.34)	(−0.88)	(0.34)
Sleep	−0.00	0.01	−0.02
	(−0.01)	(0.39)	(−0.73)
Outdoore Exercise	−0.0002	−0.01 *	−0.01
	(−0.04)	(−1.65)	(−0.98)
Middle School	0.002
	(0.05)
High School	−0.04
	(−0.45)
N	522	272	250
R2	0.08	0.15	0.08

^† Myopia is measured in absolute value of natural logarithm of the unit of refractive error (D) multiplied by 100. ^‡ Income is in natural logarithm. Space refers to respondents’ consciousness about their living space, measured on the 5-point Likert scale. A higher value means more concern that their living conditions are not spacious enough and are harmful to their (or their children’s) vision. Length refers to years since the diagnosis of myopia. Numbers shown in the table are regression coefficients with t-values in parentheses. * p < 0.1, ** p < 0.05, *** p < 0.01.