Table 3.
Logistic regression analysis predicting whether North or South Carolina residents who gave birth in North Carolina from September 28, 2018, through March 19, 2019, were added to the Early Check mailing lists by urbanicity, estimated race and ethnicity, and Early Check birth hospital affiliation
| Predictor | Letter | Postcard | ||||
|---|---|---|---|---|---|---|
| OR | SE | OR | SE | OR | SE | |
| Urbanicity (reference = rural) | ||||||
| Urban | 1.39*** | 0.11 | 1.48*** | 0.12 | 1.02 | 0.42 |
| Race/ethnicity (reference = white) | ||||||
| Black | 1.00 | 0.00 | 1.00 | 0.00 | 1.00 | 0.00 |
| American Indian | 1.00 | 0.00 | 0.98*** | 0.01 | 0.99 | 0.02 |
| Hispanic | 1.00 | 0.00 | 1.00 | 0.00 | 1.01 | 0.01 |
| Other | 1.00 | 0.00 | 1.00 | 0.00 | 1.00 | 0.01 |
| Birth hospital affiliation (reference = not affiliated) | ||||||
| Affiliated with an Early Check research partner | 2.00*** | 0.20 | 2.60*** | 0.15 | 0.82 | 0.32 |
| Constant | 31.01 | 2.36 | 0.04 | 0.00 | 161.66 | 67.91 |
| Model fit statistics | ||||||
| N | 54,887 | 54,887 | 6,433 | |||
| LL | −5,777.54 | −12,573.83 | −221.18 | |||
| χ2(6) | 75.03*** | 352.36*** | 1.78 | |||
| R2 McFadden’s | 0.01 | 0.03 | 0.01 | |||
The analysis excludes 18 women for whom geolocation data were insufficient to compute urbanicity. In the case of multiple births and repeat samples, we used location data from the earliest record for each mother.
OR, odds ratio; SE, robust standard errors that allow for clustering by census tracts.
***
p < 0.001.