Table 7 Results of the regression analyses between the BPS-J sum score and sleep-related variables

Sleep duration on workdays

 Less than 5 h

reference

reference

reference

 Less than 6 h

OR = 0.89

 < 0.001

OR = 0.89

 < 0.001

OR = 0.88

0.001

 Less than 7 h

OR = 0.81

 < 0.001

OR = 0.81

 < 0.001

OR = 0.79

 < 0.001

 Less than 8 h

OR = 0.78

 < 0.001

OR = 0.77

 < 0.001

OR = 0.75

 < 0.001

 Less than 9 h

OR = 0.88

 < 0.001

OR = 0.76

 < 0.001

OR = 0.76

0.002

 Less than 10 h

OR = 0.68

 < 0.001

OR = 0.67

 < 0.001

OR = 0.67

0.002

 10 h and over

OR = 0.8

0.25

OR = 0.73

0.1

OR = 0.70

0.09

Feeling fatigue at daytime

 0 days

reference

reference

reference

 1 – 2 days

OR = 1.02

0.24

OR = 1.02

0.19

OR = 1.03

0.1

 3 – 4 days

OR = 1.07

 < 0.001

OR = 1.08

0.002

OR = 1.10

 < 0.001

 5 – 6 days

OR = 1.07

0.01

OR = 1.07

0.02

OR = 1.09

0.008

 7 days

OR = 1.14

 < 0.001

OR = 1.14

 < 0.001

OR = 1.17

 < 0.001

Feeling sleep loss at daytime

 0 days

reference

reference

reference

 1 – 2 days

OR = 1.09

 < 0.001

OR = 1.1

 < 0.001

OR = 1.13

 < 0.001

 3 – 4 days

OR = 1.17

 < 0.001

OR = 1.17

 < 0.001

OR = 1.21

 < 0.001

 5 – 6 days

OR = 1.23

 < 0.001

OR = 1.24

 < 0.001

OR = 1.29

 < 0.001

 7 days

OR = 1.31

 < 0.001

OR = 1.32

 < 0.001

OR = 1.38

 < 0.001

Viewing bedtime procrastination as a problem

 1 not at all

reference

reference

reference

 2

OR = 0.96

0.12

OR = 0.97

0.22

OR = 0.97

0.29

 3

OR = 0.96

0.04

OR = 0.96

0.07

OR = 0.96

0.15

 4

OR = 0.96

0.048

OR = 0.97

0.18

OR = 0.98

0.4

 5 very much

OR = 0.91

 < 0.001

OR = 0.92

0.007

OR = 0.93

0.03

Munich ChronoType Questionnaire

 Sleep duration on workdays

β =—0.43

 < 0.001

β =—0.42

 < 0.001

β =—0.42

 < 0.001

 Sleep duration on work-free days

β =—0.21

 < 0.001

β =—0.21

 < 0.001

β =—0.18

 < 0.001

 Midsleep at workdays

β = 0.38

 < 0.001

β = 0.38

 < 0.001

β = 0.38

 < 0.001

 Midsleep at work-free days

β = 0.34

 < 0.001

β = 0.34

 < 0.001

β = 0.34

 < 0.001

 Absolute social jetlag

β = 0.06

0.26

β = 0.06

0.25

β = 0.08

0.10

  < 120 min

reference

reference

reference

  ≥ 120 min

OR = 1.02

0.5

OR = 1.02

0.41

OR = 1.04

0.21

 Weekly sleep loss

β = 0.11

0.03

β = 0.10

0.03

β = 0.12

0.01