Table 7.
Classifications of prenatal exposure status to amoxicillin based upon algorithm-derived gestational age versus gestational age obtained from the linked infant birth certificate files*
| Exposure status based on gestational age obtained from birth certificate files | Exposure status based on algorithm-derived gestational age
|
|||||||
|---|---|---|---|---|---|---|---|---|
| Any time during pregnancy | First trimester | Second trimester | Third trimester | |||||
| Use | Nonuse | Use | Nonuse | Use | Nonuse | Use | Nonuse | |
| All deliveries (n = 146,173) | ||||||||
| Use (n) | 20,167 | 343 | 7,806 | 593 | 8,696 | 714 | 8,422 | 544 |
| Nonuse (n) | 98 | 125,565 | 728 | 137,046 | 637 | 136,126 | 166 | 137,041 |
| Sensitivity (%) and 95% CI | 98.3 (98.1, 98.5) | 92.9 (92.4, 93.5) | 92.4 (91.9, 92.9) | 93.9 (93.4, 94.4) | ||||
| Specificity (%) and 95% CI | 99.9 (99.9, 99.9) | 99.5 (99.4, 99.5) | 100.0 (99.9, 100.0) | 99.9 (99.9, 99.9) | ||||
| PPV (%) and 95% CI | 99.5 (99.4, 99.6) | 91.5 (90.9, 92.0) | 93.2 (92.6, 93.7) | 98.1 (97.8, 98.3) | ||||
| NPV (%) and 95% CI | 99.7 (99.7, 99.8) | 99.6 (99.5, 99.6) | 99.9 (99.9, 99.9) | 99.6 (99.6, 99.6) | ||||
| Term deliveries as determined by health plan data (n = 133,568) | ||||||||
| Use (n) | 18,330 | 296 | 7,051 | 514 | 7,838 | 640 | 7,743 | 490 |
| Nonuse (n) | 88 | 114,854 | 637 | 125,366 | 559 | 124,531 | 133 | 125,202 |
| Sensitivity (%) and 95% CI | 98.4 (98.2, 98.6) | 93.2 (92.6, 93.8) | 92.5 (91.9, 93.0) | 94.0 (93.5, 94.5) | ||||
| Specificity (%) and 95% CI | 99.9 (99.9, 99.9) | 99.5 (99.5, 99.5) | 99.6 (99.5, 99.6) | 99.9 (99.9, 99.9) | ||||
| PPV (%) and 95% CI | 99.5 (99.4, 99.6) | 91.7 (91.1, 92.3) | 93.3 (92.8, 93.9) | 98.3 (98.0, 98.6) | ||||
| NPV (%) and 95% CI | 99.7 (99.7, 99.8) | 99.6 (99.6, 99.6) | 99.5 (99.4, 99.5) | 99.6 (99.6, 99.6) | ||||
| Preterm deliveries as determined by health plan data (n = 12,605) | ||||||||
| Use (n) | 1,837 | 47 | 755 | 79 | 858 | 74 | 679 | 54 |
| Nonuse (n) | 10 | 10,711 | 91 | 11,680 | 78 | 11,595 | 33 | 11,839 |
| Sensitivity (%) and 95% CI | 97.5 (96.7, 98.2) | 90.5 (88.3, 92.4) | 92.1 (90.1, 93.7) | 92.6 (90.5, 94.4) | ||||
| Specificity (%) and 95% CI | 99.9 (99.8, 100.0) | 99.2 (99.1, 99.4) | 99.3 (99.2, 99.5) | 99.7 (99.6, 99.8) | ||||
| PPV (%) and 95% CI | 99.5 (99.0, 99.7) | 89.2 (87.0, 91.3) | 91.7 (89.7, 93.4) | 95.4 (93.6, 96.8) | ||||
| NPV (%) and 95% CI | 99.6 (99.4, 99.7) | 99.3 (99.2, 99.5) | 99.4 (99.2, 99.5) | 99.5 (99.4, 99.7) | ||||
Abbreviations: CI: confidence interval; NPV: negative predictive value; PPV: positive predictive value.
*
Restricted to deliveries by women with continuous health plan enrollment and pharmacy benefits from 100 days before pregnancy through delivery.