Table 1 Distribution of emotional and behavioral problems (n = 2490)

Age (years)

0.41

2.47

0.25

0.24

1.71

0.36

 <4

538 (21.6)

62 (11.5)

36 (6.7)

56 (10.4)

91 (16.9)

152 (28.3)

61 (11.3)

 ≥4

1952 (78.4)

206 (10.6)

172 (8.0)

189 (9.7)

313 (16.0)

497 (25.5)

240 (12.3)

Gender

7.57**

3.92*

4.74*

16.07**

14.74**

18.73**

 Male

1289 (51.8)

160 (12.4)

94 (7.3)

143 (11.1)

246 (19.1)

378 (29.3)

191 (14.8)

 Female

1201 (48.2)

108 (9.0)

114 (9.5)

102 (8.5)

158 (13.2)

271 (22.6)

110 (9.2)

Any siblings

0.38

0.65

0.30

0.21

0.18

0.79

 Yes

269 (10.8)

26 (9.7)

19 (7.1)

29 (10.8)

41 (15.2)

73 (27.1)

37 (13.8)

 No

2221 (89.2)

242 (10.9)

189 (8.5)

216 (9.7)

363 (16.3)

576 (25.9)

264 (11.9)

Delivery mode

0.37

1.32

0.05

2.01

0.02

0.37

 Vaginal delivery

1233 (49.5)

128 (10.4)

95 (7.7)

122 (9.7)

187 (15.2)

320 (26.0)

152 (12.5)

 Cesarean section

1257 (50.4)

140 (11.1)

113 (9.0)

123 (10.0)

217 (17.3)

329 (26.2)

147 (11.7)

Birth weight

0.95

0.05

0.14

1.76

0.31

0.43

 Small for gestational age

247 (9.9)

25 (10.1)

21 (8.5)

23 (9.3)

44 (17.8)

68 (27.5)

30 (12.1)

 Appropriate for gestational age

1847 (74.1)

195 (10.6)

155 (8.4)

184 (10.0)

289 (15.6)

478 (25.9)

227 (12.3)

 Large for gestational age

396 (15.9)

48 (12.1)

32 (8.1)

38 (9.6)

71 (17.9)

103 (26.0)

44 (11.1)

Family income (CNY/month)

2.15

1.93

4.87

0.33

9.46**

8.20*

 < 2500

698 (28.0)

79 (11.3)

64 (9.2)

79 (11.3)

118 (16.9)

212 (30.4)

105 (15.0)

 2500–4000

1045 (42.0)

119 (11.4)

90 (8.6)

87 (8.3)

167 (16.0)

258 (24.7)

111 (10.6)

 ≥ 4000

747 (30.0)

70 (9.4)

54 (7.2)

79 (10.6)

119 (15.9)

179 (24.0)

85 (11.4)

Maximum educational level of parents

14.36**

5.56

14.07**

31.70***

19.68**

5.49

 High school or less

758 (30.4)

107 (14.1)

77 (10.2)

100 (13.2)

169 (22.3)

241 (31.8)

109 (14.4)

 College or 2-year degree

787 (31.6)

65 (8.3)

54 (6.9)

69 (8.8)

118 (15.0)

195 (24.8)

85 (10.8)

 Bachelor’s or above

945 (38.0)

96 (10.2)

77 (8.1)

76 (8.0)

117 (12.4)

213 (22.5)

107 (11.3)

Passive smoking

5.49*

9.82**

5.65*

8.46**

1.13

1.01

 Yes

397 (15.9)

56 (14.1)

49 (12.3)

52 (13.1)

84 (21.2)

112 (28.2)

42 (10.6)

 No

2093 (84.1)

212 (10.1)

159 (7.6)

193 (9.2)

320 (15.3)

537 (25.7)

259 (12.4)

Outdoor activities (h/day)

0.17

0.98

0.02

0.79

7.98**

3.52

 < 2

1355 (54.4)

149 (11.0)

120 (8.9)

133 (9.8)

228 (16.8)

384 (28.3)

179 (13.2)

 ≥ 2

1135 (45.6)

119 (10.5)

88 (7.8)

112 (9.9)

176 (15.5)

265 (23.3)

122 (10.7)