Table 2.
Association between inverse distance weighted well count within 10-mile radius of maternal residence and CHDs, NTDs, and oral clefts.
| Inverse distance weighted well counta | 0 wells within 10 miles | Low (first tertile) | Medium (second tertile) | High (third tertile) | Cochran–Armitage trend test p-valueb |
|---|---|---|---|---|---|
| Live births (n) | 66,626 | 19,214 | 19.209 | 19,793 | |
| CHDs | |||||
| Cases (n) | 887 | 281 | 300 | 355 | |
| Crude OR | 1 | 1.1 | 1.2 | 1.3 | < 0.0001 |
| Adjusted OR (95% CI)c | 1.1 (0.93, 1.3) | 1.2 (1.0, 1.3) | 1.3 (1.2, 1.5) | ||
| NTDs | |||||
| Cases (n) | 27 | 6 | 7 | 19 | |
| Crude OR | 1 | 0.77 | 0.90 | 2.4 | 0.01 |
| Adjusted OR (95% CI)d | 0.65 (0.25, 1.7) | 0.80 (0.34, 1.9) | 2.0 (1.0, 3.9) | ||
| Oral clefts | |||||
| Cases (n) | 139 | 31 | 41 | 40 | |
| Crude OR | 1 | 0.77 | 1 | 0.97 | 0.9 |
| Adjusted OR (95% CI)c | 0.65 (0.43, 0.98) | 0.89 (0.61, 1.3) | 0.82 (0.55, 1.2) | ||
| aFirst tertile, 1–3.62 wells/mile; second tertile, 3.63–125 wells/mile; third tertile, 126–1,400 wells/mile. bPerformed as two-tailed test on unadjusted logistic regression. cAdjusted for maternal age, ethnicity, smoking, alcohol use, education, and elevation of residence, as well as infant parity and sex. dAdjusted only for residence elevation because of low numbers. | |||||