Table 4.

Multivariate analysis

Variable	B	SE	Wald χ2	P	OR	95% CI
BMI	0.050	0.026	3.648	0.056	1.051	0.999-1.106
Years of employment >5	0.118	0.021	32.893	0.000	1.125	1.081-1.171
Nursing position	1.387	0.460	9.090	0.003	4.001	1.625-9.855
Frequency of night shift >4 times/month	0.280	0.474	0.350	0.554	1.324	0.523-3.352
Standing hours at work >5 h/d	0.530	0.469	1.277	0.258	1.699	0.678-4.258
Without training in low back protection	1.687	0.499	11.448	0.001	5.404	2.034-14.358
Constant	-30.457	4.731	41.446	0.000	-	-