Table 1.
Summary statistics for full dataset
| Variable | Full sample | Community water | Private well | P value for difference |
| N | 13,372 | 11,209 | 2,163 | |
| Characteristics of child | ||||
| Gender (N) (%) | 0.847 | |||
| Female | 6,658 (50.2) | 5,580 (50.2) | 1,078 (50.4) | |
| Male | 6,597 (49.8) | 5,537 (49.8) | 1,060 (49.6) | |
| Race (N) (%) | <0.001 | |||
| All other | 9,758 (73.0) | 8,044 (71.8) | 1,714 (79.2) | |
| Non-Hispanic Black | 3,614 (27.0) | 3,165 (28.2) | 449 (20.8) | |
| Age at time of Pb test, months (N) (%) | 0.259 | |||
| 0 to 8 | 93 (0.695) | 79 (0.705) | 14 (0.647) | |
| 9 to 14 | 7,324 (54.8) | 6,106 (54.5) | 1,218 (56.3) | |
| 15 to 19 | 904 (6.76) | 757 (6.75) | 147 (6.80) | |
| 20 to 29 | 1,977 (14.8) | 1,650 (14.7) | 327 (15.2) | |
| >30 | 3,074 (23.0) | 2,617 (23.3) | 457 (21.1) | |
| Age indicator (mean) (SD) | 0.798 (0.310) | 0.797 (0.311) | 0.803 (0.304) | 0.465 |
| Year of blood test (mean) (SD) | 2005 (1.88) | 2005 (1.88) | 2005 (1.86) | 0.107 |
| Blood draw type (N) (%) | 0.971 | |||
| Capillary | 1,301 (10.7) | 1,091 (10.7) | 210 (10.7) | |
| Venous | 10,815 (89.3) | 9,065 (89.3) | 1,750 (89.3) | |
| Child outcomes | ||||
| Blood Pb, µg/dL (mean) (SD) | 2.30 (1.77) | 2.36 (1.78) | 2.52 (1.65) | <0.001 |
| Blood Pb ≥ 5 µg/dL (N) (%) | 1,241 (9.28) | 1,006 (8.97) | 235 (10.9) | 0.006 |
| Any juvenile complaint (N) (%) | 415 (3.10) | 351 (3.13) | 64 (2.96) | 0.672 |
| Number of juvenile complaints (mean) (SD) | 0.122 (1.251) | 0.117 (1.223) | 0.144 (1.386) | 0.688 |
| Any serious complaint (N (%)) | 191 (1.43) | 160 (1.43) | 31 (1.43) | 0.983 |
| Number of serious complaints (mean) (SD) | 0.0462 (0.606) | 0.0435 (0.579) | 0.0587 (0.730) | 0.975 |
| Characteristics of child’s home at time of blood test | ||||
| Home value (mean) (SD) | $226,468 ($194,458) | $226,448 ($180,381) | $226,575 ($257,904) | 0.984 |
| Built before 1978 (N) (%) | 3,847 (29.7) | 3,249 (29.5) | 598 (31.0) | 0.171 |
| Year built (N) (%) | <0.001 | |||
| Before 1950 | 863 (6.66) | 739 (6.59) | 124 (6.43) | |
| 1950–1977 | 2,984 (23.0) | 2,510 (22.8) | 474 (24.6) | |
| 1978–1987 | 1,959 (15.1) | 1,676 (15.2) | 283 (14.7) | |
| 1988–1997 | 2,673 (20.6) | 2,191 (19.9) | 482 (25.0) | |
| 1998–2002 | 2,941 (22.7) | 2,599 (23.6) | 342 (17.7) | |
| 2003 or later | 1,539 (11.9) | 1,315 (11.9) | 224 (11.6) | |
| Characteristics of child’s census block group, blood test year | ||||
| Median income (mean) (SD) | $71,839 ($31,797) | $69,729 ($31,149) | $82,795 ($32,866) | <0.001 |
| % Black (mean) (SD) | 0.274 (0.233) | 0.287 (0.242) | 0.210 (0.168) | <0.001 |
| Characteristics of child’s census block group, age 14 | ||||
| Median income (mean) (SD) | $76,069 ($33,635) | $75,863 ($33,785) | $77,134 ($32,833) | 0.058 |
| % Black (mean) (SD) | 0.252 (0.224) | 0.257 (0.229) | 0.225 (0.194) | <0.001 |