ORs and 95% CIs from logistic regression analysis for the association between urinary trichlorophenols and attention deficit hyperactivity disorder among children aged 6–15 years, NHANES, 1999–2004
| Chemicals | Total sample (n) | Cases (n) | Crude odd ratios | Adjusted odd ratios* |
| 2,4,5-TCP | ||||
| Below the LOD | 1776 | 145 | Referent group | Referent group |
| <Median (1.03 μg/g) | 367 | 30 | 1.27 (0.78 to 2.06) | 1.01 (0.47 to 2.20) |
| ≥Median (1.03 μg/g) | 368 | 24 | 0.89 (0.48 to 1.65) | 0.98 (0.48 to 1.99) |
| p for trend | – | – | 0.72 | 0.95 |
| 2,4,6-TCP | ||||
| Below the LOD | 846 | 56 | Referent group | Referent group |
| <Median (3.58 μg/g) | 834 | 84 | 1.84 (1.25 to 2.72) | 1.54 (0.97 to 2.43) |
| ≥Median (3.58 μg/g) | 834 | 59 | 1.56 (1.12 to 2.16) | 1.77 (1.18 to 2.66) |
| p for trend | – | – | 0.008 | 0.006 |
↵* Adjusted for age, gender, poverty-to-income ratio, maternal smoking during pregnancy, low birth weight, blood lead and serum cotinine.
LOD, limit of detection; TCP, trichlorophenol.