Table 4

Association of trihalomethane exposure and term low birth weight (a) as reported by Gallagher et al. [7] and (b) after adjusting for 50% exposure misclassification

Exposure Category (ppb)

Number of outcomes

Number of normal deliveries

Crude OR

(a) Original Study

≤ 20*

11

614

Reference

21–40

8

346

1.3

41–60

4

188

1.2

≥ 61

6

67

5.0

All exposed

18

601

1.7

(b) With Adjustment for 50% Exposure Misclassification

≤ 20*

20

914

Reference

21–40

4

173

1.1

41–60

2

94

1.0

≥ 61

3

34

4.0

All exposed

9

301

1.4

Jones et al. Epidemiologic Perspectives & Innovations 2006 3:6   doi:10.1186/1742-5573-3-6