Oral language development is a key outcome of elementary school, and it is important to identify factors that predict it most effectively. Commonly researchers use ordinary least squares regression with conclusions restricted to average performance conditional on relevant covariates. Quantile regression offers a more sophisticated alternative.…

Research has identified risks of both poverty and affluence for adolescents. This study sought to clarify associations between income and youth mental and behavioral health by delineating economic risks derived from family, neighborhood, and school contexts within a nationally representative sample of high school students (N = 13,179, average age…

This study employs the Specificity Principle to examine the relative impacts of external (input quantity at home and at school, number of books and reading frequency at home, teachers' degree and experience, language usage, socioeconomic status) and internal factors (children's working memory, nonverbal intelligence, learning-related…

Vocabulary knowledge was tested in a native (Cantonese-Chinese) and foreign (English) language in 150 twins and 150 singletons aged 6-11 years, matched on age, gender, grade level, nonverbal intelligence, parents' education, family income, and number of siblings and household members. The singletons clearly outperformed the twins on the native…

Fifteen-year-old adolescents (N = 109) in a longitudinal study of child development were recruited to examine differences in DNA methylation in relation to parent reports of adversity during the adolescents' infancy and preschool periods. Microarray technology applied to 28,000 cytosine-guanine dinucleotide sites within DNA derived from buccal…

The development and adjustment correlates of parent-child social (parent, child, and others present) and dyadic time (only parent and child present) from age 8 to 18 were examined. Mothers, fathers, and firstborns and secondborns from 188 White families participated in both home and nightly phone interviews. Social time declined across…

Drawing from developmental and cultural adaptation perspectives and using a longitudinal design, this study examined: (a) mean-level changes in Mexican-origin adolescents' cultural orientations and adjustment from early to late adolescence and (b) bidirectional associations between cultural orientations and adjustment using a cross-lag panel…

This study examined the increase in salivary cortisol from midmorning to midafternoon in 151 children (3.0-4.5 years) in full-time home-based day care. Compared to cortisol levels at home, increases were noted in the majority of children (63%) at day care, with 40% classified as a stress response. Observations at day care revealed that intrusive,…

Differences in racial socialization practices and their effects were examined in a sample of 241 African American 1st graders (average age 6.59 years) living in an urban area. Child outcomes included cognitive development, receptive language skills, and child problem behavior. The cultural environment of the home was associated with higher…