Body temperature

Χ² value

φ

P value

Low body temperature

(n = 35)

Normal temperature

(n = 191)

n

%

Adjusted residual

n

%

Adjusted residual

Breakfast

(n = 226)

I eat breakfast every morning.

28

12.39

−2.4

177

78.32

2.4

5.63

−0.16

0.02*

I sometimes do not eat breakfast.

7

3.10

2.4

14

6.19

−2.4

Bowel movement

(n = 226)

I have bowel movement every day.

18

7.96

−1.0

116

51.33

1.0

1.06

−0.07

0.30

I do not have bowel movement every day.

17

7.52

1.0

75

33.19

1.0

School meal

(n = 226)

I always eat a full school meal.

30

13.27

3.1

111

49.12

−3.1

8.46

0.21

0.00^a)***

I sometimes leave part of a school meal.

5

2.21

−3.1

80

35.40

3.1

Snack (lunch to dinner)

(n = 226)

I eat a snack four days or more a week.

13

5.75

−0.1

73

32.30

0.1

0.02

−0.01

0.90

I eat a snack less than three days a week.

22

9.73

0.1

118

52.21

−0.1

Snack (dinner to fall asleep)

(n = 226)

I eat a snack four days or more a week.

1

0.44

−1.1

15

6.64

1.1

0.49

−0.07

0.48^a)

I eat a snack less than three days a week.

34

15.04

1.1

176

77.88

−1.1

Exercise

(n = 226)

I exercise three or more days a week.

26

11.50

−0.6

150

66.37

0.6

0.31

−0.04

0.58

I exercise less than two days a week.

9

3.98

0.6

41

18.14

−0.6

Cram school

(n = 226)

I am going to cram school.

16

7.08

−0.2

90

39.82

0.2

0.02

−0.01

0.88

I am not going to cram school.

19

8.41

0.2

101

44.69

−0.2

PSQI

(n = 226)

PSQI ≥ 6

2

0.88

−0.8

6

2.65

0.8

0.07

−0.05

0.36^a)

PSQI < 6

33

14.60

0.8

185

81.86

−0.8

Physical strength

(n = 225)

High

17

7.56

0.4

102

45.33

−0.4

0.13

0.02

0.71

Low

17

7.56

−0.4

89

39.56

0.4

Falling asleep^#

(n = 177)

I could fall asleep quickly.

19

10.73

0.0

134

75.71

0.0

0.00

0.00

1.00^a)

I had difficulty sleeping.

3

1.69

0.0

21

11.86

0.0

Wake up^##

(n = 105)

I woke up feeling refreshed.

12

11.43

0.3

69

65.71

−0.3

0.00

0.03

1.00^a)

I was sleepy.

3

2.86

−0.3

21

20.00

0.3