Chinese seafarers (Mean)

European seafarers (Mean)

Officers (Mean)

Ratings (Mean)

Age

34.18

(n = 461, SD = 9.16, S.E = 0.43)

38.06

(n = 443, SD = 10.49, S.E = 0.49)

36.66

(n = 486, SD = 9.81, S.E = 0.45)

35.57

(n = 379, SD = 10.07, S.E = 0.52)

Sailing Age

8.36

(n = 469, SD = 7.78, S.E = 0.36)

13.58

(n = 405, SD = 9.30, S.E = 0.46)

11.59

(n = 480, SD = 9.16, S.E = 0.42)

9.81

(n = 364, SD = 8.42, S.E = 0.44)

Contract work hours (weekly)

56.93

(n = 294, SD = 9.42, S.E = 0.55)

58.57

(n = 341, SD = 14.05, S.E = 0.76)

59.20

(n = 325, SD = 12.26, S.E = 0.68)

56.34

(n = 284, SD = 11.90, S.E = 0.71)

Actual work hours (weekly)

60.40

(n = 283, SD = 10.58, S.E = 0.63)

63.58

(n = 382, SD = 14.11, S.E = 0.72)

64.52

(n = 346, SD = 12.62, S.E = 0.68)

59.73

(n = 291, SD = 12.72, S.E = 0.75)

Amount of time at sea

7.91

(n = 367, SD = 1.23, S.E = 0.07)

5.32

(n = 367, SD = 1.82, S.E = 0.10)

6.13

(n = 408, SD = 2.26, S.E = 0.11)

7.29

(n = 298, SD = 1.51, S.E = 0.87)

Actual sleep

8.06

(n = 444, SD = 1.61, S.E = 0.07)

8.06

(n = 441, SD = 1.94, S.E = 0.09)

7.82

(n = 484, SD = 1.76, S.E = 0.08)

8.38

(n = 365, SD = 1.78, S.E = 0.09)

Ideal sleep

8.68

(n = 457, SD = 1.22,S.E = 0.06)

7.76

(n = 442, SD = 1.52, S.E = 0.07)

8.13

(n = 490, SD = 1.42, S.E = 0.06)

8.36

(n = 373, SD = 1.50, S.E = 0.08)

Sleep quality

1.24

(n = 472, SD = 0.59, S.E = 0.03)

0.86

(n = 452, SD = 0.47, S.E = 0.02)

1.16

(n = 501, SD = 0.56, S.E = 0.03)

0.93

(n = 386, SD = 0.55, S.E = 0.03)

Distress at work

1.39

(n = 420, SD = 0.81,S.E = 0.04)

0.73

(n = 424, SD = 0.61, S.E = 0.03)

1.21

(n = 475, SD = 0.79, S.E = 0.04)

0.87

(n = 342, SD = 0.74, S.E = 0.04)

Tiredness at work

2.17

(n = 449, SD = 0.91, S.E = 0.04)

1.71

(n = 431, SD = 0.82, S.E = 0.04)

2.09

(n = 472, SD = 0.87, S.E = 0.04)

1.78

(n = 374, SD = 0.89, S.E = 0.05)