Table 5 One-way variance analysis of different characteristics (M, SD)

Total

12.03(2.28)

11.83(2.57)

14.87(3.03)

11.60(2.23)

11.29(2.38)

11.58(2.25)

45.98(8.34)

Household registration

 Urban areas

12.25(2.32)

11.98(2.53)

15.09(3.13)

11.87(2.30)

11.41(2.51)

11.85(2.27)

46.82(8.76)

 Rural areas

11.80(2.23)

11.67(2.61)

14.64(2.91)

11.30(2.11)

11.17(2.22)

11.30(2.20)

45.06(7.76)

 F value

6.011

2.242

3.342

10.180

1.497

9.541

7.032

 P value

0.014

0.135

0.068

0.001

0.222

0.002

0.008

Monthly living expenses (CNY)

 ≤ 1000

11.90(2.29)

11.36(2.76)

14.45(2.97)

10.93(2.37)

10.84(2.55)

11.01(2.53)

43.77(8.19)

 1000–1499

12.12(2.17)

11.93(2.47)

14.86(2.95)

11.63(2.09)

11.35(2.17)

11.53(2.02)

46.15(7.93)

 1500–1999

12.00(2.56)

12.10(2.63)

15.11(3.19)

11.91(2.22)

11.74(2.41)

12.06(2.25)

47.76(8.42)

 ≥ 2000

11.99(2.24)

11.90(2.48)

15.24(3.14)

12.08(2.21)

11.20(2.59)

11.97(2.28)

46.34(9.08)

 F value

0.305

2.119

1.581

6.410

3.254

5.898

5.261

 P value

0.821

0.097

0.193

0.000

0.021

0.001

0.001

Mothers’ smoking experience

 Never smoke

12.04(2.27)

11.88(2.54)

14.91(3.04)

11.63(2.19)

11.32(2.36)

11.62(2.22)

46.10(8.35)

 Smoke

10.67(2.71)

10.58(3.20)

14.08(2.81)

10.33(3.39)

10.42(3.20)

10.50(3.26)

42.33(6.16)

 Quitted

14.25(0.96)

8.25(2.50)

12.00(1.41)

10.00(2.16)

9.50(1.73)

9.50(1.73)

39.00(8.76)

 F value

4.086

5.478

2.254

3.061

2.009

3.206

2.624

 P value

0.017

0.004

0.106

0.048

0.135

0.041

0.073

Fathers’ smoking experience

 Never smoke

12.17(2.17)

12.04(2.46)

15.31(2.98)

11.83(2.09)

11.50(2.43)

11.89(2.21)

46.93(8.17)

 Smoke

11.86(2.44)

11.69(2.66)

14.59(3.14)

11.36(2.41)

11.15(2.44)

11.33(2.38)

45.09(8.80)

 Quitted

12.21(2.03)

11.73(2.56)

14.60(2.69)

11.71(1.90)

11.20(2.00)

11.57(1.83)

46.21(7.01)

 F value

1.574

1.311

4.141

3.152

1.454

4.155

3.267

 P value

0.208

0.270

0.016

0.043

0.234

0.016

0.039