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 |