Table 3 Odds ratio and 95% confidence interval for vitamin D levels from the multivariable logistic regression (N = 1594)

 12–2

1

1

1

1

 3–5

2.228^**

1.355,3.663

2.201^**

1.328,3.648

2.257^**

1.358,3.750

2.248^**

1.350,3.743

 6–8

2.170^***

1.443,3.263

2.127^***

1.407,3.216

2.103^***

1.390,3.180

2.094^***

1.383,3.173

 9–11

2.227^**

1.336,3.714

2.115^**

1.251,3.575

2.169^**

1.282,3.671

2.104^**

1.240,3.571

 20–29

1

1

1

 30–39

2.383^***

1.558,3.916

2.414^***

1.519,3.834

2.383^***

1.494,3.800

  ≥ 40

2.279^**

1.415,4.597

2.296^**

1.242,4.243

2.279^*

1.221,4.254

 Unmarried

1

1

1

 Married or other

.991

.677,1.449

.970

.660,1.426

1.019

.689,1.507

 Diploma

1

1

1

 Bachelor

1.346

.827,2.190

1.374

.843,2.238

1.405

.860,2.295

 Master’s or higher

1.284

.709,2.326

1.355

.745,2.463

1.324

.726,2.415

 Yes

1

1

 No

1.193

.821,1.734

1.233

.847,1.797

 Overtime hours (week)

.963

.927,1.001

.964

.927,1.002

 Underweight

1

 Normal

.775

.463,1.300

 Overweight

.814

.462,1.435

 Physical activity

1.001

.996,1.005

 Minimal

1

 Mild

1.408

.967,2.051

 Moderate

1.183

.604,2.317

 Moderately severe above

2.457

.950,6.357

 Stress symptoms

.942^**

.900,.985

 Nagelkerke R²

 Chi/df