This twin study examined the genetic and environmental etiology of vocabulary, syntax, and their association in first graders. French-speaking same-sex twins (n = 555) completed two vocabulary tests, and two scores of syntax were calculated from their spontaneous speech at 7 years of age. Multivariate latent factor genetic analyses showed that…

Prior research shows that short-term effects from preschool may disappear, but little research has considered which environmental conditions might sustain academic advantages from preschool into elementary school. Using secondary data from two preschool experiments, we investigate whether features of elementary schools, particularly advanced…

Prior research shows that short-term effects from preschool may disappear, but little research has considered which environmental conditions might sustain academic advantages from preschool into elementary school. Using secondary data from two preschool experiments, we investigate whether features of elementary schools, particularly advanced…

This longitudinal study was conducted to determine (a) the rate of co-occurrence of reading disabilities (RDs) in a writing disability (WD) population of students followed from first grade to fourth grade and (b) the cognitive burden that is assumed by having a WD and a RD (WD + RD). The sample included 137 first-grade students from a single…

The purpose of this study was to compare the results of a regression discontinuity design (RDD) with those of an experimental design of a tiered vocabulary intervention for children at risk for reading disability to determine RDD's feasibility as a research methodology for this type of study. Researchers reanalyzed an archival dataset of a…

We explored the usefulness of first and second grade reading measures and responsiveness criteria collected within a response-to-intervention (RtI) framework for predicting reading disability (RD) in third grade. We used existing data from 387 linguistically diverse students who had participated in a longitudinal RtI study. Model-based predictors…

The ability to flexibly approach the pronunciation of unknown words, or set "for variability", has been shown to contribute to word recognition skills. However, this is the first study that has attempted to teach students strategies for increasing their set for variability. Beginning readers (N = 15) were instructed to correct oral…

We explored the usefulness of 1st and 2nd grade reading measures and responsiveness criteria collected within a Response-to-Intervention (RtI) framework for predicting Reading Disability (RD) in 3rd grade. We used existing data from 387 linguistically diverse students who had participated in a longitudinal RtI study. Model-based predictors of RD…

A substantial literature documents the benefits of early childhood education and formal preschool experiences on children's school readiness, with low-income and otherwise disadvantaged children benefitting the most from these programs. However, these academic benefits often fade out as children age, and most disappear by the end of kindergarten…

This study investigated the prevalence and stability of latent classes at risk for reading disabilities (RD) in elementary-aged children whose first language is Spanish. To this end, children (N = 489) in Grades 1, 2, and 3 at Wave 1 were administered a battery of reading, vocabulary, and cognitive measures (short-term memory [STM], working memory…