Skip to main content

Table 2 Serum vitamin D levels of the subjects

From: The relationship between serum vitamin D levels and sleep quality in fixed day indoor field workers in the electronics manufacturing industry in Korea

Variables

 

Vitamin D

P valuea

≥10 ng/mL

<10 ng/mL

N

%

N

%

Total

 

1040

(70.7)

432

(29.3)

 

Age, years

≥30

584

(71.8)

229

(28.2)

0.269

<30

456

(69.2)

203

(30.8)

 

Sex

Male

886

(75.2)

292

(24.8)

<0.001

Female

154

(52.4)

140

(47.6)

 

Regular exercise, times per week

≥3

405

(75.7)

130

(24.3)

0.001

<3

635

(67.8)

302

(32.2)

 

Smoking

Current

328

(76.6)

100

(23.4)

0.001

Never/former

712

(68.2)

332

(31.8)

 

Risky drinkingb

Yes

296

(77.1)

88

(22.9)

0.001

No

744

(68.4)

344

(31.6)

 

Body mass index, kg/m2

<25

668

(70.5)

280

(29.5)

0.831

≥25

372

(71.0)

152

(29.0)

 

Marital status

Married

571

(73.8)

203

(26.2)

0.006

Unmarried

469

(67.2)

229

(32.8)

 

Education level

≥College

718

(72.2)

276

(27.8)

0.055

≤High school

322

(67.4)

156

(32.6)

 

Job tenure, years

<5

321

(68.6)

147

(31.4)

0.387

5–9

277

(72.3)

106

(27.7)

 

≥10

442

(71.2)

179

(28.8)

 

Job stress

Low

807

(70.1)

344

(29.9)

0.390

High

233

(72.6)

88

(27.4)

 

Test seasonc

Spring

198

(66.0)

102

(34.0)

<0.001

Summer

400

(87.7)

56

(12.3)

 

Autumn

117

(78.0)

33

(22.0)

 

Winter

325

(57.4)

241

(42.6)

 
  1. aComparison made using the chi-square test
  2. bRisky drinking: 2 or more times per week and 7 (females: 5) or more drinks per drinking session
  3. cSpring, March–May; summer, June–August; autumn, September–November; winter, December–February
  4. Abbreviations: SD standard deviation
Back to article page

Annals of Occupational and Environmental Medicine

ISSN: 2052-4374

Contact us