Table 3 Pooled estimates of SNC relative risk and 95% confidence intervals by subgroups within exposures to wood dust, leather dust, formaldehyde and textile industry (case-control studies)

By duration of exposure

0.001

Wood dust

<15 years

18/7

2.40 (1.34-4.31)

≥15 years

39/7

9.19 (5.84-14.46)

By duration of exposure

0,371

Leather dust

<15 years

7/3

7.44 (2.55-21.70)

≥15 years*

13/4

13.30 (6.68-26.48)

By level of exposure

0.664

Formaldehyde

low

6/2

1.38 (0.92-2.06)

moderate/high

8/3

1.57 (1.00-2.48)

By duration of exposure

0.10

Textile industry

<15 years

5/3

1.79 (1.12-2.87)

≥15 years

8/3

3.31 (1.90-5.78)