Table 2 Univariate analysis of factors associated with asthma among leather tannery workers, Karachi, Pakistan, August 2003 to March 2004 (n = 641^†)

Age

641

1.06

1.02, 1.08

<0.01

Educational status

   Literate

377

1.00

-

   Illiterate

264

2.45

1.47, 4.09

<0.01

Type of house

   Pacca

582

1.00

   Katcha

57

0.78

0.30, 2.02

0.61

Ethnicity

   Punjabi

334

1.00

-

<0.01

   Pathan

211

3.32

1.91, 5.76

   Others

91

1.18

0.49, 2.86

Place of interview

   Factory

194

1.00

   Outside factory

416

2.30

1.21, 4.42

0.01

House ownership

   Owned

262

1.00

-

   Rented

376

0.96

0.58, 1.59

0.96

Smoking status

   Non-smoker

455

1.00

-

   Ever smoker

182

2.11

1.26, 3.51

0.04

Naswar use^‡

   No

150

1.00

-

   Yes

486

2.47

1.47, 4.15

0.01

Perceived allergy^§

   No

152

1.00

-

   Yes

475

3.71

2.20, 6.27

<0.01

Working hours per day

641

1.01

0.98, 1.05

0.47

Exposure to chemicals

   No

56

1.00

-

   Yes

583

0.69

0.31, 1.52

0.36

Knowledge about hazards of chemicals

   No

33

1.00

-

   Yes

543

1.15

0.39, 3.40

0.80

Glove Use

   User**

268

1.00

-

   Non-user^††

373

2.93

1.25, 4.54

<0.01

Total duration of work

641

1.08

1.04, 1.12

<0.01

Exhaust fan use

   No

127

1.00

-

   Yes

355

0.91

0.47, 1.75

0.78

Air sucker use^‡‡

   No

367

1.00

-

   Yes

115

0.68

0.32, 1.43

0.31

Water sucker use^§§

   No

411

1.00

-

   Yes

71

1.12

0.50, 2.49

0.41

Provision of gloves

   No

122

1.00

-

   Yes

447

0.78

0.42, 1.42

0.42

Provision of masks

   No

167

1.00

-

   Yes

402

0.88

0.51, 1.55

0.66

Coverage for health***

   No

437

1.00

-

   Yes

131

0.87

0.47, 1.58

0.64

Pre-placement and regular physical examination

   No

415

1.00

-

   Yes

80

0.76

0.38, 1.55

0.56