Table 1

Study population: people and areas and percent of cases geocoded, by level of geography: births in Massachusetts (1989-1991; n=267,273) and Rhode Island (1987-1993; n=94,175), and childhood lead screening* in Rhode Island (1994-1996; n=62514)

N (%)% geocoded to:
BGCTZCnot geocoded
Data source: peopleMARIMARIMARIMARIMARI
Birth:267273 (100.0)94175 (100.0)94.797.4100.0100.0100.099.90.00.0
Gender of infant:
    Boy137208 (51.3)48258 (51.2)94.697.3100.0100.0100.099.90.00.0
    Girl130282 (48.7)45917 (48.8)94.897.4100.0100.0100.099.90.00.0
Age of mother:
    15–1917578 (6.6)9588 (10.2)95.197.8100.0100.0100.099.90.00.0
    20–2450363 (18.8)22482 (23.9)94.597.7100.0100.0100.099.90.00.0
    24–2983356 (31.2)30647 (32.5)94.397.2100.0100.0100.099.90.00.0
    30–3478198 (29.3)22690 (24.1)95.097.1100.0100.0100.099.90.00.0
    35–3932119 (12.0)7719 (8.2)95.097.2100.0100.0100.099.80.00.0
    40–445485 (2.1)1003 (1.1)95.097.2100.0100.0100.099.90.00.0
    45–55174 (0.1)46 (0.0)93.6100.0100.0100.0100.0100.00.00.0
Mother’s race/ethnicity†:
    White, non-Hispanic209023 (78.5)38751 (76.2)94.198.8100.0100.0100.099.80.00.0
    Black, non-Hispanic20375 (7.7)3904 (7.7)96.999.0100.0100.0100.0100.00.00.0
    Other, non-Hispanic27836 (10.5)2260 (4.4)96.898.9100.0100.0100.099.90.00.0
    Hispanic9030 (3.4)5924 (11.7)96.099.0100.0100.0100.0100.00.00.0
Mother’s educational level (highest attained)†:
    < high school44632 (16.8)18515 (20.0)95.897.9100.0100.0100.099.90.00.0
    high school85031 (32.0)32489 (35.1)94.297.4100.0100.0100.099.90.00.0
    > high school, <4 y college63281 (23.8)17587 (19.0)94.197.0100.0100.0100.099.90.00.0
    4+ y college73004 (27.4)23955 (25.9)95.197.2100.0100.0100.099.90.00.0
Plurality:
    singleton239,564 (89.6)84995 (90.3)94.897.4100.0100.0100.099.90.00.0
    multiple27,709 (10.4)9810 (9.7)93.996.5100.0100.0100.0100.00.00.0
Birth weight†:
    <1500 g2834 (1.1)1090 (1.2)95.597.4100.0100.0100.099.90.00.0
    1500–2499 g12603 (4.7)4798 (5.1)95.297.7100.0100.0100.099.90.00.0
    2500–3499 g134605 (50.4)49081 (52.1)94.897.5100.0100.0100.099.90.00.0
    3500–4499 g111637 (41.8)37522 (39.8)94.597.1100.0100.0100.099.90.00.0
    ≥4500 g5594 (2.1)1684 (1.8)94.297.6100.0100.0100.099.80.00.0
low birth weight (<2500 g)15437 (5.8)5888 (6.3)95.297.7100.0100.0100.099.90.00.0
mean (SD)3394.9 (591.6)3363.4 (594.5)
N (%)BGCTZCnot geocoded
Data source: peoplevenouscapillaryvenouscapillaryvenouscapillaryvenouscapillaryvenouscapillary
Lead: RI only (n)31076 (100.0)31438 (100.0)92.994.293.695.193.594.96.44.9
Age:
    1 to <2 y12238 (39.4)13440 (42.8)93.794.294.495.394.295.15.64.7
    2 to <3 y6793 (21.9)6467 (20.6)92.894.793.695.493.595.26.44.6
    3 to <4 y5863 (18.9)5601 (17.8)93.694.393.395.093.194.86.75.0
    4 to <5 y6182 (19.9)5930 (18.9)91.693.592.394.592.294.37.75.5
Gender:
    Girls14841 (47.8)15093 (48.0)94.194.294.895.294.795.05.24.8
    Boys15460 (49.6)15790 (50.2)94.194.295.095.194.894.85.14.9
    unknown775 (2.5)555 (1.8)43.993.944.495.344.195.055.64.7
Race/ethnicity‡:
    White14822 (47.7)21039 (66.9)93.493.794.594.794.294.55.55.3
    Black2117 (6.8)1785 (5.7)97.596.898.197.397.896.91.92.7
    Hispanic5538 (17.8)3156 (10.0)97.998.198.198.298.198.11.91.8
    Asian911 (2.9)393 (1.3)99.198.799.199.099.198.50.91.0
    American Indian38 (0.1)84 (0.3)100.084.5100.090.597.490.50.09.5
    Other288 (0.9)572 (1.8)97.992.398.694.898.693.41.45.2
    Unknown7362 (23.7)4409 (14.0)85.592.786.493.786.393.613.66.3
Blood lead level (μg/dl):
    <2.03406 (11.0)1735 (5.5)93.894.594.695.994.495.75.44.1
    2.0–4.911643 (37.5)10390 (33.1)93.894.194.795.194.694.85.34.9
    5.0–9.910678 (34.4)12444 (39.6)94.093.994.794.894.594.65.35.2
    10.0–14.93105 (10.0)4040 (12.9)93.294.593.795.493.695.16.34.6
    15.0–19.91162 (3.7)1484 (4.7)90.495.090.895.390.895.39.24.7
    ≥20.01082 (3.5)1345 (4.3)70.095.870.496.470.396.429.63.6
Increased lead (≥10 μg/dl)5349 (17.2)6869 (21.9)87.994.888.495.688.395.411.64.4
mean (SD)6.2 (5.9)7.2 (6.5)5.9 (5.4)7.2 (6.5)5.9 (5.4)7.2 (6.5)5.9 (5.4)7.2 (6.5)9.5 (10.6)6.9 (6.0)
median5.05.05.06.05.05.05.05.05.05.0
Population sizePopulation size
Data source: areasNMean (SD)RangeNMean (SD)Range
*Restricted to a child’s first screening test during the study interval. †in MA, data were missing on mother’s race/ethnicity for 0.4% and on mother’s education for 0.5% of births; in RI, data on race/ethnicity were not included with the birth certificate data until 1990, so values for race/ethnicity refer only to births between 1990 and 1993 and do not include births from 1987 through 1989, while for mother’s education, data were missing for 1.8% of RI births during the total study interval (1987–1993). ‡Race/ethnicity: Among venous cases, Hispanics includes 333 persons identified as Portuguese (0.6%); the category “Asian” included persons categorised as Vietnamese (n=33; 3.6%), Laotian (n=248; 27.2%), Cambodian (n=512; 56.2%), and Hmong (n=118; 13.0%) Among capillary cases, Hispanics included 399 persons identified as Portuguese (1.3%); the category “Asian” included persons categorised as Vietnamese (n=40; 0.1%), Laotian (n=155; 0.5%), Cambodian (n=170; 0.5%) and Hmong (n=28; 0.1%).
Block groups56031085.4 (665.2)5 to 100968971137.7 (670.8)7 to 5652
Census tracts13314571.8 (2,080.0)18 to 154112354325.3 (1810.9)26 to 9822
zip codes47412719.7 (12,244.1)14 to 650017014335.2 (13234.8)63 to 53763