Purpose: Using data from 1,868 children from the US, Australia, and Sweden who took a 10-word spelling test in kindergarten and a standardized spelling test in Grades 1, 2, and (except for the Australian children) Grade 4, we examined two questions. First, does the quality of a child's errors on the kindergarten test help predict later spelling…

We investigated the double-deficit hypothesis (DDH) in samples of U.S. (N = 489), Australian (N = 264), and Scandinavian (N = 293) children followed from preschool to grade 2. Children were assigned to double deficit, single deficit and no deficit subtypes in preschool, kindergarten, and grade 1 and compared on reading and spelling in grades 1 and…

The main purpose of this study was to examine the classroom, teacher and student factors distinguishing grade three classes performing at higher levels than expected, in relation to socioeconomic status (SES) and language factors, from classes performing below their potential with regard to the same factors. Data from a standardized reading…

Modern behavior-genetic studies of twins in the United States, Australia, Scandinavia, and the United Kingdom show that genes account for most of the variance in children's reading ability by the end of the 1st year of formal reading instruction. Strong genetic influence continues across the grades, though the relevant genes vary for reading words…

Genetic and environmental relations between vocabulary and reading skills were explored longitudinally from preschool through Grades 2 and 4. At preschool there were strong shared-environment and weak genetic influences on both vocabulary and print knowledge but substantial differences in their source. Separation of etiology for vocabulary and…

Twin children from Australia, Scandinavia, and the United States were assessed for inattention, hyperactivity-impulsivity, and reading across the first 3 school years. Univariate behavior-genetic analyses indicated substantial heritability for all three variables in all years. Longitudinal analyses showed one genetic source operating across the…

The genetic factor structure of a range of learning measures was explored in twin children, recruited in preschool and followed to Grade 2 ("N"?=?2,084). Measures of orthographic learning and word reading were included in the analyses to determine how these patterned with the learning processes. An exploratory factor analysis of the…

Studied the effectiveness of phonological training in improving the reading of 33 poor readers in grade 4 in Sweden. Results show that some children resisted phonological training. These were students for whom only orthographic deciding skills, and not phonological decoding skills, predicted text reading before the phonological instruction. (SLD)