Table 8. Crude and adjusted logistic regression analyses with shift work disorder as the dependent variable.

		Crude	Adjusteda (N = 1560)
		OR (95% CI)	OR (95% CI)
Age		1.01 (1.00–1.03)	1.02 (1.00–1.03)
Gender	male	1.00	1.00
	female	0.69 (0.51–0.94)	0.83 (0.58–1.17)
Number of night shifts past year		1.01 (1.01–1.01)	1.01 (1.01–1.01)
Years with night work	<5	1.00	1.00
	>5	1.27 (1.04–1.57)	1.17 (0.93–1.47)
Fraction of full position	50–75%	1.00	1.00
	76–90%	0.84 (0.62–1.14)	0.95 (0.68–1.34)
	>90%	0.92 (0.75–1.13)	0.92 (0.72–1.17)
Number of quick returns past year	0	1.00	1.00
	1–30	1.68 (1.22–2.32)	1.88 (1.33–2.67)
	>30	2.53 (1.85–3.45)	2.86 (2.03–4.03)

OR =  Odds ratio.

CI =  Confidence interval.

^a)All predictor variables (age, gender, number of night shifts past year, years with night work, fraction of full position and number of quick returns past year) were entered together in the adjusted analyses.