The Wechsler Abbreviated Scale of Intelligence, Second Edition (WASI-II; Wechsler, 2011), published by Pearson, is a newly updated abbreviated measure of cognitive intelligence designed for individuals 6 to 90 years of age. Primarily used in clinical, psychoeducational, and research settings, the WASI-II was developed to quickly and accurately…

Intellectual assessment is central to the process of diagnosing an intellectual disability and the assessment process needs to be valid and reliable. One fundamental aspect of validity is that of measurement invariance, i.e. that the assessment measures the same thing in different populations. There are reasons to believe that measurement…

Research on the Wechsler Adult Intelligence Scale-Revised and Wechsler Adult Intelligence Scale-Third Edition (WAIS-III) suggests that practicing clinical psychologists and graduate students make item-level scoring errors that affect IQ, index, and subtest scores. Studies have been limited in that Full-Scale IQ (FSIQ) and examiner administration,…

This study compared the effectiveness of three different video-based instructional sequences, all used in conjunction with the system of least prompts, for teaching three different daily living skills to three young adults with developmental disabilities. The video-based instructional sequences (i.e., video rehearsal, video rehearsal plus photos,…

Professional assessment of mental retardation (MR) and learning disabilities (LD) is crucial to the implementation of P.L. 94-142 because it necessarily precedes the employment of trained teachers and because a plan for remediation depends on accurate assessment. Intelligence is a key element in the identification of MR-LD, but competent, fair…