Table 2 The descriptive characteristics of the study participants

Overall

41,620

100

9.022

4.601

30.2

2.78

0.54

62.464

19.162

Gender

Male

17,212

41.4

8.991

4.575

t=-1.158 P = 0.247

47.3

x2 = 4021.004

P < 0.001

V = 0.311

2.776

0.539

t=-1.367 P = 0.172

62.504

19.118

t=-1.158 P = 0.247

Female

24,408

58.6

9.044

4.62

18.3

2.783

0.541

62.436

19.193

Grade

Freshman

23,878

57.4

9.04

4.588

F = 0.566 P = 0.638

31.2

x2 = 63.342

P < 0.001

V = 0.039

2.777

0.537

F = 10.762 P < 0.001

62.201

19.143

F = 9.536 P < 0.001

Sophomore

10,605

25.5

9.022

4.601

30.3

2.77

0.546

62.36

19.144

Junior

5479

13.2

8.952

4.69

25.8

2.818

0.547

63.712

19.291

Senior

1658

4

8.995

4.497

31.2

2.772

0.53

62.8

18.972

Area

Eastern

14,657

35.2

9.109

4.697

F = 5.055 P = 0.001

29.6

x2 = 118.938

P < 0.001

V = 0.053

2.786

0.545

F = 14.027 P < 0.001

62.518

19.137

F = 1.410 P = 0.224

Westward

10,300

24.7

8.923

4.472

34.4

2.756

0.531

62.676

19.182

Central

16,663

40

9.007

4.594

28.2

2.79

0.542

62.286

19.171

Ethnicity

Han

38,360

92.2

9.016

4.596

t=-0.095 P = 0.335

29.6

x2 = 108.157

P < 0.001

V = 0.051

2.782

0.541

t = 2.308 P = 0.042

62.44

19.148

t=-0.892 P = 0.372

Minority

3260

7.8

9.097

4.66

38.3

2.762

0.537

62.752

19.33

BMI

Underweight

4608

11.1

9.018

4.569

F = 0.501 P = 0.682

22.7

x2 = 555.629

P < 0.001

V = 0.161

2.789

0.542

F = 0.991 P = 0.392

61.687

19.156

F = 3.652 P = 0.012

Normal

24,976

60

9.035

4.59

30.8

2.777

0.541

62.468

19.155

Overweight

5563

13.4

8.954

4.612

33.4

2.785

0.539

62.644

18.968

Obesity

6433

15.5

9.039

4.661

30.9

2.783

0.541

62.87

19.366