Table 1 Sample characteristics and the distributions of negative life events and coping styles in categorical items (N=3081)

Gender

0.113

<0.001

0.064

 Male

1565 (50.8)

52.7 (20.2)

15.4 (8.3)

6.5 (4.5)

 Female

1516 (49.2)

51.6 (18.5)

16.6 (7.9)

6.8 (4.3)

Grades

<0.001

<0.001

<0.001

 7

979 (31.8)

46.7 (17.1)

14.2 (8.4)

5.8 (4.4)

 8

1085 (35.2)

53.3 (19.7)

15.8 (7.9)

6.5 (4.3)

 9

1017 (33.0)

56.2 (19.8)

17.9 (7.7)

7.7 (4.4)

School type

<0.001

<0.001

0.704

 Urban

1552 (50.4)

50.4 (18.6)

17.0 (8.1)

6.6 (4.4)

 Rural

1529 (49.6)

54.0 (19.9)

14.9 (8.0)

6.7 (4.5)

Family type

<0.001

0.042

0.662

 Stem family

1060 (34.4)

52.6 (19.5)

16.4 (8.1)

6.7 (4.4)

 Nuclear family

1669 (54.2)

51.0 (18.9)

15.9 (8.3)

6.6 (4.5)

 Single parent family

271 (8.8)

56.4 (20.6)

15.1 (7.8)

6.8 (4.4)

 Foster family

81 (2.6)

57.3 (19.8)

15.0 (7.1)

7.0 (4.0)

Fathers’ education level

<0.001

<0.001

0.342

 Junior college or higher

334 (10.8)

48.0 (18.6)

18.2 (8.7)

6.4 (4.5)

 Senior school

671 (21.8)

50.9 (18.9)

16.8 (7.4)

6.8 (4.5)

 Junior middle school

1647 (53.5)

52.2 (18.8)

15.4 (8.2)

6.6 (4.4)

 Primary school or less

429 (13.9)

57.2(21.6)

15.1(8.0)

7.0(4.5)

Mothers’ education level

<0.001

<0.001

0.015

 Junior college or higher

252 (8.2)

48.5 (19.2)

18.3 (8.7)

6.8 (4.6)

 Senior school

464 (15.1)

51.5 (20.3)

17.4 (8.3)

6.8 (4.6)

 Junior middle school

1447 (46.9)

50.5 (17.8)

15.6 (8.1)

6.4 (4.3)

 Primary school or less

918 (29.8)

56.1 (20.6)

15.1 (7.8)

7.0 (4.5)

Smoking

<0.001

0.015

0.004

 No

3003 (97.5)

51.7 (18.8)

16.0 (8.1)

6.6 (4.4)

 Yes

78 (2.5)

71.1 (28.4)

13.8 (8.1)

8.6 (5.7)

Drinking alcohol

<0.001

0.010

<0.001

 No

2086 (67.7)

49.4 (17.7)

16.2 (8.3)

6.4 (4.4)

 Yes

995 (32.3)

57.9 (21.3)

15.4 (7.8)

7.3 (4.5)

Physical exercise

0.050

<0.001

0.208

 Lack of exercise

2251 (73.1)

52.6 (19.0)

15.0 (7.8)

6.6 (4.3)

 Often exercise

830 (26.9)

51.0 (20.1)

18.5 (8.5)

6.8 (4.7)

Self-rated health

<0.001

<0.001

<0.001

 Good

1724 (56.0)

49.4 (18.5)

16.7 (8.3)

6.5 (4.5)

 Fair

1168 (37.9)

54.4 (18.8)

14.9 (7.8)

6.7 (4.3)

 Poor

189 (6.1)

63.5 (23.8)

15.5 (8.0)

8.2 (4.9)

Self-perceived study stress

<0.001

0.020

<0.001

 Low

536 (17.4)

42.8 (15.7)

16.8 (8.9)

5.9 (4.3)

 Fair

1554 (50.4)

49.9 (17.1)

15.6 (8.0)

6.3 (4.3)

 High

991 (32.2)

60.9 (20.9)

16.0 (7.9)

7.6 (4.6)

Depressive symptoms

<0.001

0.705

<0.001

 No

2467 (80.1)

46.8 (14.8)

15.9 (8.4)

6.0 (4.1)

 Yes

614 (19.9)

73.5 (20.6)

16.1 (7.0)

9.4 (4.6)