Entwicklung parallelisierter Wortlisten zur Verlaufsdiagnostik bei dyslektischen Kindern

Objective: In the course of the long-term treatment of developmental dyslexia it is important to continuously observe the progress of the individual reader. Considering the lack of reading tests with parallel forms which can be repeatedly administered without learning effects, and which are quick to perform, this is a big challenge in German-speaking regions. The aim of this study, therefore, was to create such an instrument in the form of several parallelised word lists. At the same time, the lists should allow a specific testing of both the lexical and the non-lexical route of reading, based on items with different linguistic properties.Method: 4 parallel lists were created, each composed of a wide range of different word material. To this end, word frequency, orthographic regularity, and morphological complexity were taken into account as linguistic criteria. To ensure that the lists were parallel with regard to the 3 parameters reading rate, accuracy and preferred reading strategy, they were presented to 28 third graders in a first test series. The lists were then revised and once again presented to 24 different children for final evaluation.Results: Whereas the statistical analysis of the first test series still differed with respect to the 3 above-mentioned parameters, in the revised version of the reading lists no more significant differences were found according to the linguistic criteria. As a consequence, as soon as an independent control sample has confirmed their parallelism, the lists will be ready for use for measuring the development of individual reading skills in dyslexic children

How reliable are gray matter disruptions in specific reading disability across multiple countries and languages? insights from a large-scale voxel-based morphometry study

The neural basis of specific reading disability (SRD) remains only partly understood. A dozen studies have used voxel-based morphometry (VBM) to investigate gray matter volume (GMV) differences between SRD and control children, however, recent meta-analyses suggest that few regions are consistent across studies. We used data collected across three countries (France, Poland, and Germany) with the aim of both increasing sample size (236 SRD and controls) to obtain a clearer picture of group differences, and of further assessing the consistency of the findings across languages. VBM analysis reveals a significant group difference in a single cluster in the left thalamus. Furthermore, we observe correlations between reading accuracy and GMV in the left supramarginal gyrus and in the left cerebellum, in controls only. Most strikingly, we fail to replicate all the group differences in GMV reported in previous studies, despite the superior statistical power. The main limitation of this study is the heterogeneity of the sample drawn from different countries (i.e., speaking languages with varying orthographic transparencies) and selected based on different assessment batteries. Nevertheless, analyses within each country support the conclusions of the cross-linguistic analysis. Explanations for the discrepancy between the present and previous studies may include: (1) the limited suitability of VBM to reveal the subtle brain disruptions underlying SRD; (2) insufficient correction for multiple statistical tests and flexibility in data analysis, and (3) publication bias in favor of positive results. Thus the study echoes widespread concerns about the risk of false-positive results inherent to small-scale VBM studies