This study proposes transformation functions and matrices between coefficients in the original and reparameterized parameter spaces for an existing linear-linear piecewise model to derive the interpretable coefficients directly related to the underlying change pattern. Additionally, the study extends the existing model to allow individual…

Nonresponse bias is a widely prevalent problem for data on education. We develop a ten-step exemplar to guide nonresponse bias analysis (NRBA) in cross-sectional studies and apply these steps to the Early Childhood Longitudinal Study, Kindergarten Class of 2010-2011. A key step is the construction of indices of nonresponse bias based on proxy…

This study investigated the extent to which class-specific parameter estimates are biased by the within-class normality assumption in nonnormal growth mixture modeling (GMM). Monte Carlo simulations for nonnormal GMM were conducted to analyze and compare two strategies for obtaining unbiased parameter estimates: relaxing the within-class normality…

The piecewise latent growth models (PWLGMs) can be used to study changes in the growth trajectory of an outcome due to an event or condition, such as exposure to an intervention. When there are multiple outcomes of interest, a researcher may choose to fit a series of PWLGMs or a single parallel-process PWLGM. A comparison of these models is…

Widespread availability of rich educational databases facilitates the use of conditioning strategies to estimate causal effects with nonexperimental data. With dozens, hundreds, or more potential predictors, variable selection can be useful for practical reasons related to communicating results and for statistical reasons related to improving the…

As research on mediation has grown, so too has interest in identifying ways to assess the size of indirect effects in a mediation analysis. One such estimate -- the ratio of the indirect effect to the total effect (P[subscript M]) -- was tested in a sample of 21,297 children from the Early Childhood Developmental Study. Results showed that the two…

Background: Gross motor movement is a vital part of the growing process and ultimately plays a role in a person's ability to lead a physically active life. Researchers have analyzed the different ways in which individuals develop skills. At the heart of that discussion has been gender. Most recently, researchers have focused on the differences…

This study was conducted in order to compare loneliness and social skill levels of children with specific learning disabilities in terms of participation in sports. For this study, a screening model was used. The study group was composed of 56 children who were aged between 7 and 14 years and diagnosed with a specific learning disability (30 boys…

This study aimed to determine whether dietary patterns and feeding problems differ among children with intellectual disabilities (ID) and typically developing children (TDC) in Turkey. This cross-sectional study was conducted in 220 (112 children with ID and 108 TDC) 7-12 aged children in Konya, Turkey. We assessed usual dietary intakes by a…

Nonnormality of univariate data has been extensively examined previously (Blanca et al., 2013; Micceri, 1989). However, less is known of the potential nonnormality of multivariate data although multivariate analysis is commonly used in psychological and educational research. Using univariate and multivariate skewness and kurtosis as measures of…

Physical activity is essential for youth's health, growth, and development; however, only 42% of children in the United States meet physical activity recommendations. Piloted in spring 2016, "WeCook: Fun with Food and Fitness" engaged at-risk youth in physical activity, food preparation, and nutrition education. The objective was to…

Complex surveys are often used to estimate causal effects regarding the effects of interventions or exposures of interest. Propensity scores (Rosenbaum & Rubin, 1983) have emerged as one popular and effective tool for causal inference in non-experimental studies, as they can help ensure that groups being compared are similar with respect to a…

Several studies have linked specific learning disorders (SLDs) with suicidal ideation, but less is known about the disorders' association with suicide attempts. This gap in the literature is addressed via the 2012 nationally representative Canadian Community Health Survey (n = 21,744). The prevalence of lifetime suicide attempts among those with…

Responding to a robust body of literature suggesting that children's early educational experiences are critical, policymakers have implemented and expanded the provision of full-day kindergarten (FDK) in recent decades. Most studies have focused on the effectiveness of FDK on child academic assessments or test scores, but none have examined FDK…

Turkey has been facing with migration for various reasons. More than half of those migrating from Syria to Turkey are children. In this study, it was aimed to examine the levels of PTSD, empathy and depression in Syrian children. A total of 121 boys and 135 girls from Altindag district of Ankara formed a sample group of 256 children. Personal…