Table 2.

Distribution of work-related variables, as well as fatigue, need for recovery, and sleep problems during the offshore working period

	Day shift (n = 25)				Night shift (n = 20)				Swing shift (n = 16)				F (df)	p
n	%	Mean	(SD)	n	%	Mean	(SD)	n	%	Mean	(SD)
Job demands (1–5)			3.2	(0.5)			3.2	(0.4)			3.0	(0.5)	0.57 (2,58)	0.567
Job control (1–5)			3.0	(0.8)			2.7	(0.6)			2.7	(0.3)	1.52 (2,57)	0.229
Offshore experience (y)			13.0	(8.3)			11.8	(5.1)			13.0	(7.6)	0.19 (2,57)	0.826
Checklist individual strength (20–140)			64.6	(16.0)			73.0	(20.6)			63.1	(22.8)	1.41 (2,56)	0.253
Problems with falling asleep
Never/sometimes	22	88.0			18	90.0			14	87.5			0.07 (2)	0.967
Often/every day	3	12.0			2	10.0			2	12.5
Disturbed/restless sleep
Never/sometimes	17	68.0			11	55.0			8	50.0			1.51 (2)	0.471
Often/every day	8	32.0			9	45.0			8	50.0
Problems awakening
Never/sometimes	22	88.0			18	90.0			14	87.5			0.07 (2)	0.967
Often/every day	3	12.0			2	10.0			2	12.5
Thoughts of my job keep me awake
Never/sometimes	24	96.0			19	95.0			15	93.7			0.12 (2)	0.948
Often/every day	1	4.0			1	5.0			1	6.3
Need for recovery (0–100)
< 55	17	70.8			14	70.0			14	87.5			1.82 (2)	0.402
≥ 55	7	29.2			6	30.0			2	12.5
Overtime
≤ 14 h	14	56.0			12	60.0			15	93.7			7.01 (2)	0.030
> 14 h	11	44.0			8	40.0			1	6.3
Paid work in free period
No	17	68.0			15	75.0			13	81.3			0.90 (2)	0.635
Yes, sometimes or always	8	32.0			5	25.0			3	18.7

SD, standard deviation.