To date, studies using cross-sectional methodologies make up a majority of the literature surrounding children with autism spectrum disorders and participation in physical activity and screen time. Longitudinal studies are needed to examine how physical activity and screen time behaviors co-develop for children with and without an autism spectrum…

Fragile X syndrome (FXS) is characterized by both social approach and social avoidance. However, the age of emergence and developmental trajectory of social avoidance has not been examined. This study investigates the longitudinal developmental trajectory and dynamic nature of social avoidance in males with FXS from infancy through young adulthood…

Self-regulation is a critical component of school readiness and success. Practices for supporting self-regulation may be advanced by a better understanding of factors characterizing children at risk for challenges and contextual mechanisms associated with desirable developmental trajectories. The current study leverages a large national data set…

Very preterm birth (<32 weeks of gestation) heightens the risk for developmental and behavioral problems, but individual outcomes vary greatly. We evaluated whether mother-toddler dyadic interaction quality, assessed longitudinally at 14, 20, and 30 months (corrected), could account for unique variance in very preterm and full-term children's…

Self-regulation is an essential ability of children to cope with various developmental challenges. This study examines the developmental interplay between emotional and behavioral self-regulation during childhood and the relationship with academic achievement using data from the longitudinal Millennium Cohort Study (UK). Using cross-lagged panel…

Research suggests that individuals with autism spectrum disorder (ASD) have significant difficulties with adaptive behavior skills including daily living and functional communication skills. Few studies have examined the developmental trajectory of adaptive behavior across childhood and adolescence. The present study examined longitudinal…

In this paper, we examine the impact of U.S. child-care subsidies on the cognitive and behavioral development of children in low-income female-headed families. We identify the effect of subsidy receipt by exploiting geographic variation in the distance that families must travel from home to reach the nearest social service agency that administers…

Juveniles who have committed a sexual offense (JSOs) are thought to have abnormal sexual development, as well as increased ASD symptoms. In the current study, sexual development and behavior, as well as stability of ASD-like symptoms were assessed in a sample of 44 male JSOs (mean age 24.7 ± 1.5 years) 8 years after their sexual offence. JSOs…

This study exploits a randomized trial of two light-touch elementary school interventions to estimate long-run impacts on postsecondary attendance and attainment. The first is a classroom management technique for developing behavioral skills in children. The second is a curricular intervention aimed at improving students' core reading skills. We…

This article, using longitudinal data from the National Child Development Study, presents new evidence on the effects of family size and birth order on test scores and behavioral development at age 7, 11 and 16. Sibling size is shown to have an adverse causal effect on test scores and behavioral development. For any given family size, first-borns…

The article presents 30-year bibliometrical results on trends in the scope, internationality, and impact of the "International Journal of Behavioral Development" ("IJBD") from its inception in 1978 to 2007. Bibliometric data were collected using the databases PsycINFO and Social Science Citation Index (SSCI), and the "IJBD" itself. In comparison…

The predictive relations between social capital depth (high-quality relationships across contexts) and breadth (friendship network extensivity) and early-adult life adjustment outcomes were examined using data from a prospective longitudinal study. Interviews at age 22 yielded (a) psychometrically sound indexes of relationship quality with…

This study examined how the manifestation of overt aggression changes during early adolescence using Hierarchical Linear Modeling. The distinct courses of physical and verbal aggression identified in this study provide support for developmental transformations in overt aggression, which would have been obscured unless aggression had been defined…

The timing of having one's first child, in relation to the timing of other transitions into adulthood and to social functioning, was investigated based on the Finnish Jyvaskyla Longitudinal Study of Personality and Social Development, conducted from age 8 (173 females and 196 males) to 42. Results showed that in women, relatively early (less than…

The current study investigated child behavioral change during the early years of elementary school. Behavioral Assessment System for Children (BASC; Reynolds & Kamphaus, 1992) teacher ratings of child behavior were collected over a three-year period. The sample consisted of 162 children measured yearly between first and third grade.…