Table 2.
Change in Maternally Reported and Child-Assessed Neurodevelopmental Outcome Scores per 10-Fold Increase in Mean Total Gestational Urinary Dialkyl Phosphate Concentration (nmol/L) (From Repeated-Measures (Generalized Estimating Equations) Models), Overall and by Sex, CHAMACOS Study, 1999–2000
| Assessmentand Outcome | Orientation a | Child Ages at Assessment, years | Total | Boys | Girls | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| No. of Children | No. of Obs | β | 95% CI | No. of Children | No. of Obs | β | 95% CI | No. of Children | No. of Obs | β | 95% CI | P for Interaction | |||
| Maternal reportb,c | |||||||||||||||
| BRIEF (t scores)d | 7, 9, and 12 | ||||||||||||||
| Behavior Regulation Index | Higher | 347 | 978 | 3.5 | 1.7, 5.3 | 163 | 460 | 5.7 | 2.9, 8.6 | 184 | 518 | 2.0 | −0.2, 4.2 | 0.06 | |
| Metacognition Index | Higher | 347 | 978 | 3.8 | 2.1, 5.6 | 163 | 460 | 5.4 | 2.8, 8.0 | 184 | 518 | 2.9 | 0.6, 5.1 | 0.19 | |
| Global Executive Composite | Higher | 347 | 978 | 4.0 | 2.1, 5.8 | 163 | 460 | 6.0 | 3.3, 8.8 | 184 | 518 | 2.7 | 0.4, 4.9 | 0.10 | |
| CADS (t scores)d | 7, 9, and 12 | ||||||||||||||
| ADHD Index | Higher | 349 | 988 | 2.2 | 0.8, 3.6 | 163 | 464 | 2.1 | 0.1, 4.1 | 186 | 524 | 2.3 | 0.4, 4.3 | 0.77 | |
| DSM-IV Total Scale | Higher | 349 | 988 | 2.1 | 0.5, 3.6 | 163 | 464 | 2.7 | 0.6, 4.9 | 186 | 524 | 1.7 | −0.4, 3.9 | 0.58 | |
| Inattentive | Higher | 349 | 988 | 2.0 | 0.7, 3.3 | 163 | 464 | 2.5 | 0.7, 4.4 | 186 | 524 | 1.8 | −0.1, 3.6 | 0.64 | |
| Hyperactive/Impulsive | Higher | 349 | 988 | 1.9 | 0.2, 3.5 | 163 | 464 | 2.7 | 0.3, 5.1 | 186 | 524 | 1.3 | −0.9, 3.6 | 0.45 | |
| BASC-2 (t scores)d | 7 and 10.5 | ||||||||||||||
| Hyperactivity | Higher | 335 | 634 | 1.8 | 0.4, 3.2 | 157 | 294 | 3.4 | 1.0, 5.8 | 178 | 340 | 0.8 | −0.8, 2.4 | 0.12 | |
| Attention Problems | Higher | 335 | 634 | 2.9 | 1.0, 4.8 | 157 | 294 | 2.5 | −0.3, 5.3 | 178 | 340 | 3.0 | 0.5, 5.6 | 0.71 | |
| Child assessmentb,e | |||||||||||||||
| WISC-IV (standardized scores)d | 7 and 10.5 | ||||||||||||||
| Processing Speed Index | Lower | 334 | 605 | −1.8 | −4.2, 0.6 | 157 | 283 | −2.9 | −7.2, 1.5 | 177 | 322 | −0.6 | −3.4, 2.2 | 0.27 | |
| Working Memory Index | Lower | 334 | 605 | −3.8 | −6.2, −1.3 | 157 | 283 | −4.9 | −8.8, −0.9 | 177 | 322 | −2.4 | −5.6, 0.7 | 0.48 | |
| WCST (t scores)d | 9 and 12 | ||||||||||||||
| Errors | Lower | 325 | 630 | −3.6 | −5.5, −1.7 | 153 | 295 | −2.3 | −5.3, 0.6 | 172 | 335 | −3.7 | −6.1, −1.2 | 0.58 | |
| Perseverative errors | Lower | 325 | 630 | −3.7 | −6.3, −1.2 | 153 | 295 | −2.8 | −6.8, 1.3 | 172 | 335 | −3.9 | −7.1, −0.7 | 0.80 | |
| CPT II (t scores)d | 9 and 12 | ||||||||||||||
| Errors of omission | Higher | 325 | 634 | 1.8 | −0.3, 3.9 | 153 | 297 | 2.1 | −1.3, 5.6 | 172 | 337 | 1.3 | −1.4, 4.0 | 0.32 | |
| Errors of commission | Higher | 325 | 634 | 1.6 | −0.3, 3.4 | 153 | 297 | −0.1 | −3.3, 3.0 | 172 | 337 | 3.0 | 0.6, 5.3 | 0.07 | |
| Hit rate standard error | |||||||||||||||
| Overall | Higher | 325 | 634 | 1.5 | −0.4, 3.4 | 153 | 297 | 1.9 | −1.1, 4.9 | 172 | 337 | 1.2 | −1.4, 3.7 | 0.86 | |
| By block | Higher | 325 | 634 | 1.5 | −0.5, 3.6 | 153 | 297 | 2.8 | 0.2, 5.5 | 172 | 337 | 1.1 | −1.9, 4.1 | 0.56 | |
| By interstimulus interval | Higher | 325 | 634 | 2.3 | 0.5, 4.1 | 153 | 297 | 2.4 | 0.0, 4.8 | 172 | 337 | 2.4 | −0.1, 4.9 | 0.84 | |
| ADHD Confidence Indexf | Higher | 325 | 634 | 1.1 | −2.5, 4.6 | 153 | 297 | 1.8 | −3.8, 7.3 | 172 | 337 | 0.1 | −4.6, 4.8 | 0.55 | |
Abbreviations: ADHD, attention-deficit/hyperactivity disorder; BASC-2, Behavior Assessment System for Children, Second Edition; BRIEF, Behavior Rating Inventory of Executive Function; CADS, Conners ADHD/DSM-IV Scales; CHAMACOS, Center for the Health Assessment of Mothers and Children of Salinas; CI, confidence interval; CPT II, Conners Continuous Performance Test II; DSM-IV, Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition; Obs, observations; WISC-IV, Weschler Intelligence Scale for Children—Fourth Edition; WCST, Wisconsin Card Sorting Test.
a Higher scores indicate more symptomatic behavior; lower scores indicate poorer performance.
b All models adjusted for maternal age, duration of residence in the United States (years), education, receptive language, and average depression score at child’s ages 7–9 years; average Home Observation Measurement of the Environment (HOME) score (child’s ages 7–12 years); child’s age at assessment; and child’s sex.
c Parental report models additionally adjusted for language of questionnaire administration.
d BRIEF, CADS, BASC-2, WCST, and CPT II t scores are standardized to the mean score: 50 (standard deviation, 10); WISC-IV t-standardized scores are standardized to the mean WISC-IV score: 100 (standard deviation, 15).
e Child testing models additionally adjusted for psychometrician who administered the test, language of testing, and, for the CPT II and WCST models only, video game usage.
f The CPT II ADHD Confidence Index is not a t score but rather is produced by discriminant function analysis and represents the percentage of children with this performance profile who would be correctly classified as having ADHD.