ABSTRACT
The study used a large sample of elementary schoolchildren in Russia (N = 3,448, 51.6% were girls, with a mean age of 8.70 years, ranging 6-11 years) to investigate the congruency, format and heterogeneity effects in a nonsymbolic comparison test and between-individual differences in these effects with generalized linear mixed effects models (GLMMs). The participants were asked to compare two arrays of figures of different colours in spatially separated or spatially intermixed formats. In addition, the figures could be similar or different for the two arrays. The results revealed that congruency (difference between congruent and incongruent items), format (difference between mixed and separated formats) and heterogeneity (difference between homogeneous and heterogeneous conditions) interacted. The heterogeneity effect was higher in the separated format, while the format effect was higher for the homogeneous condition. The separated format produced a greater congruency effect than the mixed format. In addition, the congruency effect was lower in the heterogeneous condition than in the homogeneous condition. Analysis of between-individual differences revealed that there was significant between-individual variance in the format and congruency effects. Analysis of between-grade differences revealed that accuracy improved from grade 1 to grade 4 only for congruent trials in separated formats. Consequently, the congruency effect increased in separated/homogeneous and separated/heterogeneous conditions. In general, the study demonstrated that the test format and heterogeneity affected accuracy and that this effect varied for congruent and incongruent items.
ABSTRACT
In this study, we considered two subscales of attention problem (AP) behaviour, inattentiveness and hyperactivity/impulsivity, as latent traits, extreme values of which indicate attention deficit hyperactivity disorder (ADHD). We examined gender differences in these traits in a community sample of Russian schoolchildren and estimated the extent to which the association of AP behaviour and math achievement varied for boys and girls. The data from a three-wave longitudinal study of math achievement of 958 children (49 % girls) were used, and growth in math achievement was estimated. The levels of inattentiveness and hyperactivity/impulsivity of each child were measured based on teachers' responses using the Behaviour Rating Scale (BRS). The results demonstrated that inattentiveness had a negative association with math achievement, while hyperactivity/impulsivity was positively associated with math achievement when inattentiveness was controlled for. Inattentiveness was negatively associated with math achievement in both boys and girls. However, the size of this association decreased over time for boys, so the gap between boys with high inattentiveness and low inattentiveness decreased from grade 1 to grade 2. Meanwhile, for girls, the association between inattentiveness and math remained stable, so the gap between girls with high inattentiveness and girls with low inattentiveness did not change.
