Table 3. Crude and adjusted logistic regression analyses with insomnia as the dependent variable.

		Crude	Adjusteda (N = 1579)
		OR (95% CI)	OR (95% CI)
Age		1.00 (0.99–1.01)	1.00 (0.98–1.01)
Gender	male	1.00	1.00
	female	0.89 (0.66–1.20)	0.87 (0.62–1.22)
Number of night shifts past year		1.00 (1.00–1.00)	1.00 (1.00–1.00)
Years with night work	<5	1.00	1.00
	>5	0.95 (0.78–1.16)	0.99 (0.80–1.23)
Fraction of full position	50–75%	1.00	1.00
	76–90%	1.23 (0.92–1.64)	1.34 (0.96–1.86)
	>90%	1.45 (1.18–1.77)	1.36 (1.07–1.72)
Number of quick returns past year	0	1.00	1.00
	1–30	1.41 (1.06–1.87)	1.44 (1.06–1.96)
	>30	1.67 (1.27–2.21)	1.57 (1.16–2.12)