A Latent Class IRT Approach to Defining and Measuring Language Proficiency.

English language learner (EL) status has high stakes implications for determining when and how ELs should be evaluated for academic achievement. In the US, students designated as English learners are assessed annually for English language proficiency (ELP), a complex construct whose conceptualization has evolved in recent years to reflect more precisely the language demands of content area achievement as reflected in the standards of individual states and state language assessment consortia, such as WIDA and ELPA21. The goal of this paper was to examine the possible role for and utility of using content area assessments to validate language proficiency mastery criteria.

Simulation of LD Identification Accuracy Using a Pattern of Processing Strengths and Weaknesses Method With Multiple Measures.

We investigated the classification accuracy of learning disability (LD) identification methods premised on the identification of an intraindividual pattern of processing strengths and weaknesses (PSW) method using multiple indicators for all latent constructs. Known LD status was derived from latent scores; values at the observed level identified LD status for individual cases according to the concordance/discordance method. Agreement with latent status was evaluated using (a) a single indicator, (b) two indicators as part of a test-retest "confirmation" model, and (c) a mean score.

Cognitive Difficulties in Struggling Comprehenders and their Relation to Reading Comprehension: A Comparison of Group Selection and Regression-Based Models.

Difficulties suppressing previously encountered, but currently irrelevant information from working memory characterize less skilled comprehenders in studies in which they are matched to skilled comprehenders on word decoding and nonverbal IQ. These "extreme" group designs are associated with several methodological issues. When sample size permits, regression approaches permit a more accurate estimation of effects.

Designing Intervention Studies: Selected Populations, Range Restrictions, and Statistical Power.

An appropriate estimate of statistical power is critical for the design of intervention studies. Although the inclusion of a pretest covariate in the test of the primary outcome can increase statistical power, samples selected on the basis of pretest performance may demonstrate range restriction on the selection measure and other correlated measures. This can result in attenuated pretest-posttest correlations, reducing the variance explained by the pretest covariate.

Are Child Cognitive Characteristics Strong Predictors of Responses to Intervention? A Meta-Analysis.

We conducted a meta-analysis of 28 studies comprising 39 samples to ask the question, "What is the magnitude of the association between various baseline child cognitive characteristics and response to reading intervention?" Studies were located via literature searches, contact with researchers in the field, and review of references from the National Reading Panel Report. Eligible participant populations included at-risk elementary school children enrolled in the third grade or below. Effects were analyzed using a shifting unit of analysis approach within three statistical models: cognitive characteristics predicting growth curve slope (Model 1, mean r r = .