Lateral preferences for hand clasping and arm folding are associated with handedness in two large-sample latent variable analyses.

Hand clasping (HC) and arm folding (AF) are bilateral limb postures which are subject to lateral preferences. Previous research suggested that left HC and left AF are "canonical" among European populations, i.e., generally preferred by right-handers. However, evidence on the associations of handedness with HC and AF to date is sparse and inconsistent, with studies mostly relying on relatively small sample sizes and arbitrary classifications of handedness. Utilizing latent class analysis for handedness classification, we present data from two large and independent middle-European samples, a discovery (n = 7,658) and replication (n = 5,062) sample. Our results indicate that right HC, not left HC, is overall preferred and that right-handedness is associated with right HC/left AF, and left- and mixed-handedness with left HC/right AF. Moreover, lateral preferences increased with age, and men had a higher preference of right HC, independent of handedness. We discuss our findings with regard to the generalizability of previous results.

Testing the Local Independence Assumption of the Rasch Model With Q 3-Based Nonparametric Model Tests.

Local independence is a central assumption of commonly used item response theory models. Violations of this assumption are usually tested using test statistics based on item pairs. This study presents two quasi-exact tests based on the Q 3 statistic for testing the hypothesis of local independence in the Rasch model. The proposed tests do not require the estimation of item parameters and can also be applied to small data sets. The authors evaluate the tests with three simulation studies. Their results indicate that the quasi-exact tests hold their alpha level under the Rasch model and have higher power against different forms of local dependence than several alternative parametric and nonparametric model tests for local independence.

What Do You Think You Are Measuring? A Mixed-Methods Procedure for Assessing the Content Validity of Test Items and Theory-Based Scaling.

The valid measurement of latent constructs is crucial for psychological research. Here, we present a mixed-methods procedure for improving the precision of construct definitions, determining the content validity of items, evaluating the representativeness of items for the target construct, generating test items, and analyzing items on a theoretical basis. To illustrate the mixed-methods content-scaling-structure (CSS) procedure, we analyze the Adult Self-Transcendence Inventory, a self-report measure of wisdom (ASTI, Levenson et al., 2005). A content-validity analysis of the ASTI items was used as the basis of psychometric analyses using multidimensional item response models (N = 1215). We found that the new procedure produced important suggestions concerning five subdimensions of the ASTI that were not identifiable using exploratory methods. The study shows that the application of the suggested procedure leads to a deeper understanding of latent constructs. It also demonstrates the advantages of theory-based item analysis.

Development of a scale to assess knowledge about suicide postvention using item response theory.

Knowledge about suicide postvention (KSPV) is an important distal outcome in the evaluation of suicide prevention programs that focus on the bereaved. However, most scales are specifically tailored to the evaluation study in question and psychometric properties are often unsatisfactory. Therefore, we developed the KSPV scale. Scale properties were investigated with Rasch trees, a newly developed method in the framework of item response theory. Additionally, we provide cues for convergent validity. In summary, the scale shows satisfactory properties for assessing KSPV and could be used to evaluate suicide postvention programs more effectively.