Cluster-wise regression analyses of the association between CBCL ADHP score, NEPSY-II-NL ATT/EF score and cortical thickness*
| Cluster | Detection | Retention | Retained for mediation anaysis§ | ||||||
|---|---|---|---|---|---|---|---|---|---|
| CBCL ADHP and cortical thickness | NEPSY-II-NL ATT/EF and cortical thickness clusters identified with CBCL ADHP | ||||||||
| b (95% CI) | β | p value† | Model R2‡ | b (95% CI) | β | p value§ | Model R2‡ | ||
| Left hemisphere | |||||||||
| Caudal middle frontal | −0.04 (−0.06 to −0.02) | −0.14 | < 0.001 | 0.05 | 0.04 (−0.01 to 0.10) | 0.06 | 0.12 | 0.04 | No |
| Right hemisphere | |||||||||
| Postcentral | −0.05 (−0.06 to −0.03) | −0.22 | < 0.001 | 0.09 | 0.02 (−0.02 to 0.06) | 0.04 | 0.34 | 0.04 | No |
| Lateral occipital | −0.05 (−0.07 to −0.03) | −0.19 | < 0.001 | 0.06 | 0.05 (−0.01 to 0.10) | 0.06 | 0.09 | 0.03 | Yes |
| Superior temporal | −0.05 (−0.07 to −0.03) | −0.16 | < 0.001 | 0.07 | 0.01 (−0.05 to 0.07) | 0.02 | 0.64 | 0.04 | No |
| Cuneus | −0.04 (−0.06 to −0.02) | −0.15 | < 0.001 | 0.06 | 0.00 (−0.05 to 0.05) | 0.00 | 0.96 | 0.04 | No |
| Cluster | NEPSY-II-NL ATT/EF and cortical thickness | CBCL ADHP and cortical thickness clusters identified with NEPSY-II-NL ATT/EF | Retained for mediation anaysis§ | ||||||
| b (95% CI) | β | p value† | Model R2‡ | b (95% CI) | β | p value§ | Model R2‡ | ||
| Left hemisphere | |||||||||
| None found | — | — | — | — | N/A | N/A | N/A | N/A | N/A |
| Right hemisphere | |||||||||
| None found | — | — | — | — | N/A | N/A | N/A | N/A | N/A |
ADHP = attention-deficit/hyperactivity problems; ATT/EF = attention and executive functioning; CBCL = Child Behavior Checklist; CI = confidence interval; N/A = not applicable; NEPSY = Developmental Neuropsychological Assessment.
↵* The CBCL ADHP and NEPSY ATT/EF scores were square root transformed, therefore b values are not interpretable. Both determinant (CBCL/NEPSY) and outcome (thickness) were residualized for age during assessment/scanning. Analyses adjusted for child sex, nationality, gestational age at birth, birth weight, psychostimulant use, IQ, maternal education, drinking during pregnancy, smoking during pregnancy and household income. A higher CBCL ADHP score indicates more attention and hyperactivity symptoms, and a higher NEPSY score indicates better functioning.
↵† To identify clusters in the discovery phase, the α level was set to 0.05.
↵‡ The explained variance (model R2) is provided for the whole model, including covariates.
↵§ To define clusters as consistent and select them for the mediation analysis, the α level was set to 0.1 (association at trend level or significant).