Skip to main content

Table 1 Differences in maternal and child characteristics in Wayne County Health, Environment, Allergy and Asthma Longitudinal Study participants with and without the 10–12 year questionnaire data, before and after inverse probability weighting (IPW)

From: Prenatal pet keeping and caregiver-reported attention deficit hyperactivity disorder through preadolescence in a United States birth cohort

Covariate   Completed the 10–12-Year Questionnaire Before IPW After IPW
No
N = 613
Yes
N = 645
Pa Db Pa Db
Maternal Characteristic   Mean ± SD or N (%)     
 Age at delivery (years)   28.9 ± 5.1 30.2 ± 5.3 < 0.001 0.25 0.642 0.02
 Race White 133 (21.7%) 157 (24.3%) 0.570 0.10 0.962 0.03
Black 387 (63.1%) 391 (60.6%)
Hispanic 40 (6.5%) 38 (5.9%)
Arabic 31 (5.1%) 28 (4.3%)
Mixed/Other 22 (3.6%) 31 (4.8%)
 Marital status Unmarried 273 (44.5%) 212 (32.9%) < 0.001 0.24 0.335 0.04
Married 340 (55.5%) 433 (67.1%)
 Insurance coverage HAP 169 (27.6%) 333 (51.6%) < 0.001 0.71 0.815 0.04
Other insurance 198 (32.3%) 233 (36.1%)
No insurance 9 (1.5%) 6 (0.9%)
Refused/do not know/missing 237 (38.7%) 73 (11.3%)
 Household income <$20,000 112 (18.3%) 70 (10.9%) < 0.001 0.32 0.938 0.05
$20,000- < $40,000 150 (24.5%) 145 (22.5%)
$40,000- < $80,000 173 (28.2%) 174 (27.0%)
$80,000- < $100,000 49 (8.0%) 86 (13.3%)
≥$100,000 52 (8.5%) 96 (14.9%)
Refused to answer 77 (12.6%) 74 (11.5%)
 Education <HS diploma 50 (8.2%) 24 (3.7%) < 0.001 0.41 0.967 0.02
HS diploma 131 (21.4%) 97 (15.0%)
Some college 313 (51.1%) 292 (45.3%)
≥Bachelor’s degree 119 (19.4%) 232 (36.0%)
 Mother smoked during pregnancy No 517 (84.3%) 591 (91.6%) < 0.001 − 0.23 0.420 − 0.03
Yes 96 (15.7%) 54 (8.4%)
 ETS during pregnancy No 421 (68.7%) 490 (76%) 0.004 −0.16 0.666 −0.02
Yes 192 (31.3%) 155 (24%)
 Prenatal alcohol use No 590 (96.6%) 616 (95.7%) 0.405 0.05 0.330 −0.04
Yes 21 (3.4%) 28 (4.3%)
 Location of residence Suburban 250 (40.8%) 305 (47.3%) 0.020 −0.13 0.224 −0.05
Urban 363 (59.2%) 340 (52.7%)
 Doctor-diagnosed hay fever or allergic rhinitis No 516 (85.0%) 538 (84.9%) 0.941 0.001 0.613 0.02
Yes 91 (15.0%) 96 (15.1%)
 Doctor-diagnosed asthma No 492 (80.3%) 513 (79.7%) 0.790 0.01 0.584 0.02
Yes 121 (19.7%) 131 (20.3%)
 Prenatal indoor dog(s) No 476 (77.7%) 479 (74.3%) 0.160 0.08 0.797 −0.01
Yes 137 (22.3%) 166 (25.7%)
 Prenatal indoor cat(s) No 520 (84.8%) 535 (82.9%) 0.364 0.05 0.538 0.02
Yes 93 (15.2%) 110 (17.1%)
Clinical Characteristics        
 Mode of delivery Vaginal 385 (63.4%) 399 (62.1%) 0.616 0.03 0.513 −0.03
C-section 222 (36.6%) 244 (37.9%)
 Firstborn No 401 (65.4%) 397 (61.6%) 0.155 0.08 0.986 −0.001
Yes 212 (34.6%) 248 (38.4%)
 Child sex Male 308 (50.3%) 314 (48.7%) 0.560 0.03 0.557 0.02
Female 304 (49.7%) 331 (51.3%)
 Gestational age at delivery (weeks)c   38.7 ± 1.8
(N = 595)
38.8 ± 1.7
(N = 637)
0.307 0.05 0.902 0.004
 Birthweight (grams)c   3258 ± 548
(N = 567)
3346 ± 594
(N = 615)
0.008 0.15 0.880 −0.006
 Completed 2-year clinic visit No 425 (69.3%) 137 (21.2%) < 0.001 1.10 0.596 0.02
Yes 188 (30.7%) 508 (78.8%)
  1. ETS environmental tobacco smoke, HAP Health Alliance Plan, HS high school, SD standard deviation
  2. aCalculated using chi-square test for categorical covariates and analysis of variance for continuous covariates. Bold values indicate statistically significant P<0.05
  3. bStandardized difference (difference in means or proportions divided by standard error); imbalance defined as absolute value> 0.20
  4. cContinuous covariates with missing data, sample size is presented