Coefficient omega indices are model-based composite reliability estimates that have become increasingly popular. A coefficient omega index estimates how reliably an observed composite score measures a target construct as represented by a factor in a factor-analysis model; as such, the accuracy of omega estimates is likely to depend on correct…

The reliability of a test score is usually underestimated and the deflation may be profound, 0.40 - 0.60 units of reliability or 46 - 71%. Eight root sources of the deflation are discussed and quantified by a simulation with 1,440 real-world datasets: (1) errors in the measurement modelling, (2) inefficiency in the estimator of reliability within…

This technical manual describes the purpose and intended uses of the TOEFL iBT test, its target test-taker population, and relevant language use domains. The test design and scoring procedures are presented first, followed by a research agenda intended to support the interpretation and use of test scores. Given the updates to the test starting…

This study aims at identifying the effect of multiple-choice test items' difficulty degree on the reliability coefficient and the standard error of measurement depending on the item response theory IRT. To achieve the objectives of the study, (WinGen3) software was used to generate the IRT parameters (difficulty, discrimination, guessing) for four…

Despite several psychometric advantages over the 50-item Autism Spectrum Quotient, an instrument used to measure autistic traits, the abridged AQ-28 and its cross-cultural validity have not been examined as extensively. Therefore, this study aimed to examine the factor structure and measurement invariance of the AQ-28 in 818 Dutch (M[subscript…

Item characteristics can have a significant effect on survey data quality and may be associated with measurement error. Literature on data quality and measurement error is often inconclusive. This could be because item characteristics used for detecting measurement error are not coded unambiguously. In our study, we use a systematic coding…

The computerized adaptive tests (CAT) apply an adaptive process in which the items are tailored to individuals' ability scores. The multidimensional CAT (MCAT) designs differ in terms of different item selection, ability estimation, and termination methods being used. This study aims at investigating the performance of the MCAT designs used to…

The present study sought to examine the psychometric properties of the French and German versions of the Physical Self-Concept Questionnaire for Elementary School Children-Revised (PSCQ-C-R). A sample of 519 children participated in this study. Of those, 197 were French-Canadian and 322 were German. Results support the factor validity and…

Comparatively little research exists on single-skill math (SSM) curriculum-based measurements (CBMs) for the purpose of monitoring growth, as may be done in practice or when monitoring intervention effectiveness within group or single-case research. Therefore, we examined a common variant of SSM-CBM: 1 digit × 1 digit multiplication. Reflecting…

Evidence of student growth is a primary outcome of interest for educational accountability systems. When three or more years of student test data are available, questions around how students grow and what their predicted growth is can be answered. Given that test scores contain measurement error, this error should be considered in growth and…

In this article, we present the results of three question design experiments on inter-item correlations, which tested a grid design against a single-item design. The first and second experiments examined the inter-item correlations of a set with five and seven items, respectively, and the third experiment examined the impact of the question design…

This study examines measurement invariance of student perceptions of teaching quality collected in five countries: Indonesia (n students = 6,331), the Netherlands (n students = 6,738), South Africa (n students = 3,422), South Korea (n students = 6,997) and Spain (n students = 4,676). The administered questionnaire was the My Teacher Questionnaire…

The objective of this study was to develop Physics critical thinking skill test using computerized adaptive test (CAT) based on item response theory (IRT). This research was a development research using 4-D (define, design, develop, and disseminate). The content validity of the items was proven using Aiken's V. The test trial involved 252 students…

The "2016 Knowledge for Teaching Early Elementary Mathematics" (2016 K-TEEM) test measures teachers' mathematical knowledge for teaching early elementary mathematics. The 2016 K-TEEM is the third version of the K-TEEM (Schoen, Bray, Wolfe, Tazaz, & Nielsen, 2017). In this report, we present results of the first large-scale field test…

Simulations were conducted to examine the effect of differential item functioning (DIF) on measurement consequences such as total scores, item response theory (IRT) ability estimates, and test reliability in terms of the ratio of true-score variance to observed-score variance and the standard error of estimation for the IRT ability parameter. The…