Measurement of Recovery after Traumatic Brain Injury: A Cognitive-Neuropsychological Comparison of the WAIS-R with the Cognitive Assessment System (CAS) in a Single Case of Atypical Language Lateralization

Latent factor structure of the Das-Naglieri Cognitive Assessment System: a confirmatory factor analysis in a Chinese setting

This study aims to measure the psychometric properties of the Das-Naglieri Cognitive Assessment System (D-N CAS) and to determine its clinical utility in a Chinese context. Confirmatory factor analysis (CFA) was conducted to examine the construct validity of the Chinese version of the D-N CAS among a group of 567, normally developed children. Test-retest reliability was examined in a random subsample of 30 children at a five-week interval. The clinical discrimination of the D-N CAS was also examined by comparing children with and without ADHD (18 children in each group) and by comparing children with and without Chinese reading disabilities (18 children in each group). The current Chinese sample demonstrated a four-factor solution for cognitive performance among children with normal development: Planning, Attention, Simultaneous processing and Successive processing (χ2(48)=91.90, p=.000; χ2/df=1.92, RMSEA=.050, GFI=.966, CFI=.954). Moreover, all subtests of the battery demonstrated acceptable test-retest reliability (r=.72-.90, p<.01) at a five-week interval among the subjects of the small subsample. Children with ADHD performed significantly worse than normal children on the Attention factor (p<.001) and the Planning factor (p<.05) of the D-N CAS, and children with Chinese reading disabilities performed significantly worse than normal children on the Simultaneous processing factor (p<.01), the Successive processing factor (p<.001) and the Planning factor (p<.05) of the D-N CAS. These findings suggested that the current four-factor structure of the D-N CAS was similar to the original factor structure of the test. The latent factor of the D-N CAS was fairly stable across the cultures. Moreover, the D-N CAS can distinguish between children with ADHD or Chinese reading disabilities and normally developed children.

A review and empirical study of the composite scales of the Das-Naglieri cognitive assessment system

Alexander Luria’s model of the working brain consisting of three functional units was formulated through the examination of hundreds of focal brain-injury patients. Several psychometric instruments based on Luria’s syndrome analysis and accompanying qualitative tasks have been developed since the 1970s. In the mid-1970s, JP Das and colleagues defined a specific cognitive processes model based directly on Luria’s two coding units termed simultaneous and successive by studying diverse cross-cultural, ability, and socioeconomic strata. The cognitive assessment system is based on the PASS model of cognitive processes and consists of four composite scales of Planning–Attention–Simultaneous–Successive (PASS) devised by Naglieri and Das in 1997. Das and colleagues developed the two new scales of planning and attention to more closely model Luria’s theory of higher cortical functions. In this paper a theoretical review of Luria’s theory, Das and colleagues elaboration of Luria’s model, and the neural correlates of PASS composite scales based on extant studies is summarized. A brief empirical study of the neuropsychological specificity of the PASS composite scales in a sample of 33 focal cortical stroke patients using cluster analysis is then discussed. Planning and simultaneous were sensitive to right hemisphere lesions. These findings were integrated with recent functional neuroimaging studies of PASS scales. In sum it was found that simultaneous is strongly dependent on dual bilateral occipitoparietal interhemispheric coordination whereas successive demonstrated left frontotemporal specificity with some evidence of interhemispheric coordination across the prefrontal cortex. Hence, support for the validity of the PASS composite scales was found as well as for the axiom of the independence of code content from code type originally specified in 1994 by Das, Naglieri, and Kirby.