Descriptive statistics for individual and sibling birth samples occurring in Pennsylvania Marcellus Shale districts by period
| . | All Births . | Sibling Sample . | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| . | Preboom (2007) . | Postboom (2012) . | Preboom (2005–2007) . | Postboom (2012–2013) . | ||||||||||
| . | Mean/ Proportion . | SD . | n . | Mean/ Proportion . | SD . | n . | Mean/ Proportion . | SD . | n . | Mean/ Proportion . | SD . | n . | ||
| Pregnancy-Related Health | ||||||||||||||
| Smoking | ||||||||||||||
| Prepregnancy (=1) | .290 | .454 | 37,325 | .254 | .436 | 39,955*** | .299 | .458 | 6,128 | .280 | .449 | 6,110* | ||
| Any trimester (=1) | .232 | .422 | 37,272 | .200 | .400 | 39,849*** | .240 | .427 | 6,125 | .237 | .425 | 6,085 | ||
| Prepregnancy weight | ||||||||||||||
| Underweight (=1) | .046 | .209 | 30,676 | .042 | .202 | 31,579* | .063 | .242 | 5,350 | .036 | .185 | 5,025*** | ||
| Overweight/obese (=1) | .454 | .498 | 30,676 | .478 | .500 | 31,579 | *** | .405 | .491 | 5,350 | .525 | .499 | 5,025*** | |
| Gestational weight gain | ||||||||||||||
| Low (=1) | .185 | .388 | 28,405 | .190 | .392 | 29,250 | .190 | .392 | 4,857 | .216 | .412 | 4,624** | ||
| High (=1) | .136 | .343 | 28,405 | .122 | .327 | 29,250*** | .144 | .351 | 4,857 | .106 | .308 | 4,624*** | ||
| Prenatal care utilization | ||||||||||||||
| First trimester (=1) | .765 | .424 | 29,188 | .778 | .415 | 35,057*** | .733 | .443 | 4,934 | .745 | .436 | 4,828 | ||
| Adequate or more (=1) | .712 | .453 | 28,097 | .740 | .439 | 29,281*** | .688 | .463 | 4,767 | .715 | .451 | 4,726** | ||
| Birth Outcomes | ||||||||||||||
| Birth weight | ||||||||||||||
| Very low (=1) | .011 | .103 | 37,710 | .009 | .092 | 40,113** | .011 | .102 | 6,186 | .007 | .086 | 6,154† | ||
| Low (=1) | .062 | .242 | 37,310 | .061 | .239 | 40,113 | .063 | .242 | 6,186 | .058 | .234 | 6,154 | ||
| Weight (grams) | 3,312.18 | 564.19 | 37,310 | 3,330.23 | 556.10 | 40,113*** | 3,306.25 | 567.98 | 6,186 | 3,353.23 | 556.28 | 6,154*** | ||
| Gestation length | ||||||||||||||
| Premature birth (=1) | .082 | .274 | 37,758 | .073 | .260 | 40,435*** | .072 | .259 | 6,195 | .075 | .263 | 6,193 | ||
| Gestation (weeks) | 38.614 | 1.958 | 37,284 | 38.728 | 1.891 | 40,095*** | 38.738 | 2.003 | 6,108 | 38.625 | 1.786 | 6,147*** | ||
| Birthing Parent Characteristics | ||||||||||||||
| Age | 27.658 | 5.978 | 37,769 | 27.997 | 5.806 | 40,437*** | 24.692 | 4.940 | 6,195 | 30.782 | 4.929 | 6,195*** | ||
| Educational attainment | ||||||||||||||
| High school diploma or less (=1) | .406 | .491 | 37,607 | .372 | .483 | 40,275*** | .518 | .500 | 6,156 | .436 | .496 | 6,175*** | ||
| Some college (=1) | .291 | .454 | 37,607 | .281 | .449 | 40,275** | .245 | .430 | 6,156 | .293 | .455 | 6,175*** | ||
| College degree or more (=1) | .303 | .460 | 37,607 | .347 | .476 | 40,275*** | .237 | .425 | 6,156 | .271 | .444 | 6,175*** | ||
| Married (=1) | .600 | .490 | 37,754 | .593 | .491 | 40,262* | .515 | .500 | 6,192 | .624 | .484 | 6,193*** | ||
| Non-Hispanic White (=1) | .854 | .353 | 37,532 | .839 | .368 | 40,300*** | .834 | .372 | 6,148 | .833 | .373 | 6,159 | ||
| First live birth (=1) | .418 | .493 | 37,669 | .429 | .495 | 40,330** | .545 | .498 | 6,179 | .000 | .000 | 6,195*** | ||
| . | All Births . | Sibling Sample . | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| . | Preboom (2007) . | Postboom (2012) . | Preboom (2005–2007) . | Postboom (2012–2013) . | ||||||||||
| . | Mean/ Proportion . | SD . | n . | Mean/ Proportion . | SD . | n . | Mean/ Proportion . | SD . | n . | Mean/ Proportion . | SD . | n . | ||
| Pregnancy-Related Health | ||||||||||||||
| Smoking | ||||||||||||||
| Prepregnancy (=1) | .290 | .454 | 37,325 | .254 | .436 | 39,955*** | .299 | .458 | 6,128 | .280 | .449 | 6,110* | ||
| Any trimester (=1) | .232 | .422 | 37,272 | .200 | .400 | 39,849*** | .240 | .427 | 6,125 | .237 | .425 | 6,085 | ||
| Prepregnancy weight | ||||||||||||||
| Underweight (=1) | .046 | .209 | 30,676 | .042 | .202 | 31,579* | .063 | .242 | 5,350 | .036 | .185 | 5,025*** | ||
| Overweight/obese (=1) | .454 | .498 | 30,676 | .478 | .500 | 31,579 | *** | .405 | .491 | 5,350 | .525 | .499 | 5,025*** | |
| Gestational weight gain | ||||||||||||||
| Low (=1) | .185 | .388 | 28,405 | .190 | .392 | 29,250 | .190 | .392 | 4,857 | .216 | .412 | 4,624** | ||
| High (=1) | .136 | .343 | 28,405 | .122 | .327 | 29,250*** | .144 | .351 | 4,857 | .106 | .308 | 4,624*** | ||
| Prenatal care utilization | ||||||||||||||
| First trimester (=1) | .765 | .424 | 29,188 | .778 | .415 | 35,057*** | .733 | .443 | 4,934 | .745 | .436 | 4,828 | ||
| Adequate or more (=1) | .712 | .453 | 28,097 | .740 | .439 | 29,281*** | .688 | .463 | 4,767 | .715 | .451 | 4,726** | ||
| Birth Outcomes | ||||||||||||||
| Birth weight | ||||||||||||||
| Very low (=1) | .011 | .103 | 37,710 | .009 | .092 | 40,113** | .011 | .102 | 6,186 | .007 | .086 | 6,154† | ||
| Low (=1) | .062 | .242 | 37,310 | .061 | .239 | 40,113 | .063 | .242 | 6,186 | .058 | .234 | 6,154 | ||
| Weight (grams) | 3,312.18 | 564.19 | 37,310 | 3,330.23 | 556.10 | 40,113*** | 3,306.25 | 567.98 | 6,186 | 3,353.23 | 556.28 | 6,154*** | ||
| Gestation length | ||||||||||||||
| Premature birth (=1) | .082 | .274 | 37,758 | .073 | .260 | 40,435*** | .072 | .259 | 6,195 | .075 | .263 | 6,193 | ||
| Gestation (weeks) | 38.614 | 1.958 | 37,284 | 38.728 | 1.891 | 40,095*** | 38.738 | 2.003 | 6,108 | 38.625 | 1.786 | 6,147*** | ||
| Birthing Parent Characteristics | ||||||||||||||
| Age | 27.658 | 5.978 | 37,769 | 27.997 | 5.806 | 40,437*** | 24.692 | 4.940 | 6,195 | 30.782 | 4.929 | 6,195*** | ||
| Educational attainment | ||||||||||||||
| High school diploma or less (=1) | .406 | .491 | 37,607 | .372 | .483 | 40,275*** | .518 | .500 | 6,156 | .436 | .496 | 6,175*** | ||
| Some college (=1) | .291 | .454 | 37,607 | .281 | .449 | 40,275** | .245 | .430 | 6,156 | .293 | .455 | 6,175*** | ||
| College degree or more (=1) | .303 | .460 | 37,607 | .347 | .476 | 40,275*** | .237 | .425 | 6,156 | .271 | .444 | 6,175*** | ||
| Married (=1) | .600 | .490 | 37,754 | .593 | .491 | 40,262* | .515 | .500 | 6,192 | .624 | .484 | 6,193*** | ||
| Non-Hispanic White (=1) | .854 | .353 | 37,532 | .839 | .368 | 40,300*** | .834 | .372 | 6,148 | .833 | .373 | 6,159 | ||
| First live birth (=1) | .418 | .493 | 37,669 | .429 | .495 | 40,330** | .545 | .498 | 6,179 | .000 | .000 | 6,195*** | ||
Note: Two-tailed tests were conducted of early versus later observations within each sample.
p < .10; *p < .05; **p < .01; ***p < .001