Table 2.
Descriptive statistics for gestational age and co-exposure variables.
| Variable | N | Min | Mean | Max | SD |
|---|---|---|---|---|---|
| Gestational Age (weeks) | 534,798 | 30.0 | 38.8 | 42.0 | 1.6 |
| Ozone Trimester 1 (ppm) | 458,130 | 0.02 | 0.04 | 0.08 | 0.01 |
| Ozone Trimester 2 (ppm) | 460,151 | 0.02 | 0.04 | 0.08 | 0.01 |
| Ozone Trimester 3 (ppm) | 460,239 | 0.02 | 0.05 | 0.09 | 0.01 |
| PM10 Trimester 1 (µg/m3) | 475,166 | 4.8 | 23.1 | 63.6 | 4.4 |
| PM10 Trimester 2 (µg/m3) | 474,702 | 4.8 | 23.0 | 60.9 | 4.3 |
| PM10 Trimester 3 (µg/m3) | 473,888 | 3.1 | 23.0 | 64.4 | 4.6 |
| Non-Smoke PM2.5 Trimester 1 (µg/m3) | 534,798 | 1.8 | 7.1 | 15.2 | 1.6 |
| Non-Smoke PM2.5 Trimester 2 (µg/m3) | 534,798 | 1.8 | 7.0 | 14.4 | 1.6 |
| Non-Smoke PM2.5 Trimester 3 (µg/m3) | 534,798 | 1.8 | 6.9 | 19.7 | 1.6 |
| Wildfire Smoke PM2.5 Trimester 1 (µg/m3) | 534,798 | 0.0 | 0.2 | 3.3 | 0.4 |
| Wildfire Smoke PM2.5 Trimester 2 (µg/m3) | 534,798 | 0.0 | 0.2 | 3.0 | 0.4 |
| Wildfire Smoke PM2.5 Trimester 3 (µg/m3) | 534,798 | 0.0 | 0.2 | 4.5 | 0.4 |
| Temperature Deviation Trimester 1 (°F) | 500,887 | −44.0 | 0.1 | 18.5 | 2.2 |
| Temperature Deviation Trimester 2 (°F) | 502,681 | −67.6 | −0.1 | 20.1 | 2.1 |
| Temperature Deviation Trimester 3 (°F) | 503,105 | −68.0 | 0.0 | 17.8 | 2.2 |