Ó£»¨ÊÓƵ

Gender

 F±ð³¾²¹±ô±ð

2.37±0.92

0.001

12.21±2.46

0.004

 M²¹±ô±ð

2.34±0.93

12.12±2.58

Age(years)

 6´Ê8

2.44±0.91

<0.001

12.61±2.43

<0.001

 9´Ê11

2.22±0.98

12.50±2.45

12~14

2.34±0.92

11.93±2.53

 15´Ê17

2.44±0.87

10.95±2.39

Residence

 R³Ü°ù²¹±ô

2.23±0.95

<0.001

11.92±2.62

<0.001

 U°ù²ú²¹²Ô

2.43±0.90

12.31±2.44

Region

 N´Ç°ù³Ù³ó

2.36±0.97

<0.001

12.11±2.48

<0.001

 C±ð²Ô³Ù±ð°ù

2.31±0.91

12.12±2.58

â€Çȴdzܳٳó

2.56±0.85

12.16±2.52

Living arrangement

 Live with parents

2.36±0.92

<0.001

12.24±2.49

<0.001

 N´Çt live with parents

2.26±0.98

11.37±2.73

Children situation (one child)

 Y±ð²õ

2.41±0.91

<0.001

12.22±2.49

<0.001

 N´Ç

2.24±0.95

12.06±2.57

Household income (monthly)

 Less than 5000 yuan

2.28±0.95

<0.001

11.98±2.59

<0.001

 5000-12000 yuan

2.42±0.90

12.30±2.45

 more than 12000 yuan

2.48±0.89

12.37±2.47

 Unwilling to answer/don't know

2.31±0.94

12.15±2.52

Mother's age

 ≤35 years

2.34±0.94

0.001

12.43±2.46

<0.001

 35-45 years

2.37±0.92

11.98±2.55

 ≥45 years

2.32±0.92

11.86±2.46

Father's age

 ≤35 years

2.32±0.94

<0.001

12.50±2.45

<0.001

 35-45 years

2.36±0.93

12.06±2.54

 ≥45 years

2.38±0.90

11.94±2.52

Mother's education level

 Junior high school and below

2.21±0.94

<0.001

11.94±2.60

<0.001

 High school/vocational school

2.40±0.93

12.25±2.48

 Junior college/bachelor's degree and above

2.56±0.87

12.48±2.37

Father's education level

 Junior high school and below

2.20±0.95

<0.001

11.90±2.60

<0.001

 High school/vocational school

2.37±0.91

12.28±2.50

 Junior college/bachelor's degree and above

2.56±0.88

12.44±2.39