The present study assessed the impact of sample size on the power and fit of structural equation modeling applied to functional brain connectivity hypotheses. The data consisted of time-constrained minimum norm estimates of regional brain activity during performance of a reading task obtained with magnetoencephalography. Power analysis was first conducted for an autoregressive model with 5 latent variables (brain regions), each defined by 3 indicators (successive activity time bins). A series of simulations were then run by generating data from an existing pool of 51 typical readers (aged 7.5-12.5 years). Sample sizes ranged between 20 and 1,000 participants and for each sample size 1,000 replications were run. Results were evaluated using chi-square Type I errors, model convergence, mean RMSEA (root mean square error of approximation) values, confidence intervals of the RMSEA, structural path stability, and Δ-Fit index values. Results suggested that 70 to 80 participants were adequate to model relationships reflecting close to not so close fit as per MacCallum et al.’s recommendations. Sample sizes of 50 participants were associated with satisfactory fit. It is concluded that structural equation modeling is a viable methodology to model complex regional interdependencies in brain activation in pediatric populations.

The purpose of the present study was to predict and explain the academic cheating behaviors of elementary school students with learning disabilities (LD) by applying the cusp catastrophe model. Participants were 32 students with identified LD from state governmental agencies although all both them and the typical students participated in the experimental manipulation (N = 480). Academic cheating was assessed using an empirical paradigm where true achievement was subtracted from achievement in a test without proper invigilation. Data analysis supported the proposed cusp catastrophe models, where mastery-related motives acted as asymmetry and performance goals as bifurcation variables respectively. These findings were confirmed with application of the interactive goal hypothesis (Barron & Harackiewicz, 2001), where the interactive approach and avoidance performance goal term functioned as a splitting factor in the relationship between adaptive motivation and performance.

The purpose of the present study was to evaluate a bullying prevention program that involved eleven 90-minute, highly structured workshops conducted at the classroom level on a weekly basis. The intervention aimed to increase student awareness of bullying and its impact, increase empathy toward victims, and enhance positive attitudes toward school and academic achievement. Participants were 666 students who were selected from 20 elementary schools using stratified random-sampling procedures from a large metropolitan area of southern Greece. Students were randomly assigned to experimental and control groups and were provided measures of bullying and victimization behaviors at pretest and posttest (Olweus, 1996). Results indicated that there were statistically significant decreases in bullying and victimization behaviors from pretest to posttest. Specifically, victimization rates in the experimental group were reduced from pretest to posttest by 55.4%. The respective decreases in the control group were 23.3%. Similarly, bullying rates decreased by 55.6% at posttest compared with pretest in the experimental group, and the combined type decreased by 66.7%. Furthermore, a latent class analysis provided qualitative means on the specific categories in which decreases of negative behaviors were observed. Additional positive effects were observed with increases in positive attitudes toward school (school liking). We conclude that the current prevention program effectively reduced bullying and victimization in the elementary schools in Greece and holds promise for influencing the overall school experience.