Table 3

Odds Ratio (OR) and 95% Confidence Interval (CI) for hearing threshold of greater than 25 dB at 4000 Hz in the better ear with logistic regression

variable

B

S.E.

Sig.

OR (95% CI)

Age

≤ 40 (n = 153)

1.0

> 40 (n = 259)

0.982

0.312

0.002

2.7 (1.4–4.9)

Exposure duration

≤ 10 (n = 70)

1.0

11–20 (n = 177)

1.139

0.462

.014

3.1 (1.3–7.7)

≥ 21 (n = 165)

1.699

0.474

< 0.001

5.5(2.1–13.8)

Smoking (pack/year)

Non smoker(n = 206)

1.0

≤ 10 (n = 105)

1.401

0.297

< 0.001

4 (2.2–7.2)

> 10 (n = 101)

3.041

0.346

< 0.001

21 (10.6–41.2)

constant

-3.400

0.493

< 0.001

0.033

R square = 0.47

Pouryaghoub et al. BMC Public Health 2007 7:137   doi:10.1186/1471-2458-7-137