Parent-Reported Attention Deficit/Hyperactivity Symptomatology in Preschool-Aged Children: Factor Structure, Developmental Change, and Early Risk Factors

Although Attention Deficit/Hyperactivity Disorder (ADHD) has increasingly been studied in preschool-aged children, relatively
few studies have provided a comprehensive evaluation of the factor structure and patterns of developmental changes in parent-reported
ADHD symptomatology across the early childhood period. This study used confirmatory factor analyses to test for longitudinal
measurement invariance of ADHD symptoms and semi-parametric finite mixture models to identify prototypic patterns of developmental
changes in ADHD symptomatology from 3 to 5 years of age. Participants were 1155 children and their parents who participated
in a prospective longitudinal study involving a representative sample of children who resided in six non-metropolitan counties
in the United States. Results indicated that (1) ADHD symptomatology was best represented by a single latent factor that exhibited
partial measurement invariance from 3 to 5 years of age, (2) 8.5 % of children exhibited sustained high levels of ADHD symptoms
from age 3–5 years, and (3) a variety of risk factors differentiated children with sustained high from those with sustained
low levels of ADHD, relatively few (most notably caregiver education) were able to differentiate children with sustained high
levels of ADHD symptoms from all other groups. Children who exhibit persistent ADHD symptomatology across the early childhood
period may define a clinically important group for etiologic research and/or early intervention efforts.