Table 1 Demographic variables Demographical characteristics and lifestyle variables among students in the SHoT-2018 study stratified by weekday-to-weekend sleep duration group

Sex, female

2549

(68.5)

7012

(69.3)

11,595

(65.7)

1914

(67.7)

6589

(72.4)

1874

(74.0)

31,533

(68.6)

Age groups

 18–20 years

522

(14.0)

1887

(18.7)

2767

(15.9)

506

(17.9)

1784

(19.8)

578

(23.2)

8044

(17.5)

 21–22 years

931

(25.0)

3054

(30.2)

5355

(30.7)

921

(32.6)

3103

(34.5)

842

(33.7)

14,206

(30.9)

 23–25 years

1121

(30.1)

3038

(30.0)

6025

(34.6)

883

(31.2)

2932

(32.6)

760

(30.4)

14,759

(32.1)

 26–28 years

552

(14.8)

1221

(12.1)

2155

(12.4)

312

(11.0)

787

(8.8)

223

(8.9)

5250

(11.4)

 29–35 years

537

(14.4)

781

(7.7)

1125

(6.5)

170

(6.0)

388

(4.3)

93

(3.7)

3094

(6.7)

Relationship status

 Single

2101

(56.4)

5221

(51.6)

8766

(49.7)

1610

(57.0)

3929

(43.3)

1107

(43.8)

22,734

(49.5)

Has children

557

(15.5)

480

(4.7)

825

(4.7)

172

(6.1)

158

(1.7)

43

(1.7)

2235

(4.9)

AUDIT

 Normal

1623

(43.6)

4117

(40.7)

7845

(44.4)

925

(32.7)

4272

(47.0)

1194

(47.2)

19,976

(43.5)

 Hazardous

2100

(56.4)

5998

(59.3)

9811

(55.6)

1902

(67.3)

4826

(53.0)

1338

(52.8)

25,975

(56.5)

Chronotype preference

 Morningness

436

(11.7)

608

(6.0)

2060

(11.7)

268

(0.9.5)

593

(6.5)

131

(5.2)

4096

(8.9)

 Intermediate

2062

(55.4)

5722

(56.6)

11,577

(65.7)

1743

(61.7)

5926

(65.3)

1510

(59.9)

28,540

(62.1)

 Eveningness

1204

(32.3)

3761

(37.2)

3974

(22.6)

805

(28.5)

2557

(28.2)

881

(34.9)

13,182

(28.7)

Delayed Sleep Phase Syndrome

0

(0.0)

137

(1.4)

70

(0.4)

8

(0.3)

40

(0.4)

7

(0.3)

262

(0.6)

Insomnia complaints

2043

(54.9)

4635

(45.8)

4109

(23.3)

773

(27.3)

2029

(22.3)

475

(18.8)

14,064

(30.6)

Overweight/Obese

1391

(39.1)

3561

(36.7)

5098

(29.9)

942

(34.6)

2666

(30.5)

759

(31.2)

14,417

(32.6)

Somatic burden

1836

(52.7)

3997

(42.0)

4013

(24.2)

808

(31.0)

2188

(25.5)

637

(26.7)

13,479

(31.2)

Dissatisfied with life

1866

(50.1)

4088

(40.4)

4996

(28.3)

972

(34.4)

2505

(27.5)

767

(30.3)

15,194

(33.1)

Failed study exam

1511

(40.6)

3745

(37.0)

5481

(31.0)

1045

(37.0)

2666

(29.3)

886

(35.0)

15,334

(33.4)

Sleep duration mean

5:30

0:59

6:44

0:40

7:58

0:27

8:13

1:04

8:32

0:27

9:51

0:34

7:44

1:11

Sleep duration weekdays

5:26

1:08

6:03

0:49

7:52

0:33

8:36

1:06

8:02

0:35

9:46

0:38

7:27

1:20

Sleep duration weekend

5:44

1:04

8:28

1.00

8:15

0:33

6:16

1:12

9:48

0:36

10:03

0:45

8:26

1:21

Sleep duration need

7:37

1:28

7:54

1:17

7:56

0:58

8:04

1:13

8:17

1:05

8:42

1:16

8:01

1:10

Sleep deficit weekday

-2:12

1:51

-1:51

1:34

-0:05

1:04

0:32

1:25

-0:15

1:13

1:04

1:17

-0:35

1:38

Sleep deficit weekend

-1:53

1:49

0:34

1:28

0:18

1:05

-0:47

1:33

1:31

1:10

1:20

1:21

0:25

1:35