The Wechsler Adult Intelligence Scale-IV: Research Challenges
The Wechsler-Bellevue Scale was released in 1939 and it has recently been revised in its most 4th edition (Wechsler Adult Intelligence Scale-IV (WAIS-IV). The WAIS Intelligence Scale despite has been in use for over 69 years, and yet, is still considered one of the most reliable and valid tools for the measurement of cognitive skills. WAIS revisions largely reflect modern approaches not only to the examination of intelligence, but also to the reduction of previous methodological errors. The latest WAIS version is characterized by smart improvements along with a solid theoretical basis. Many of the improvements are related to its developmental suitability so that the performance of the subject is not affected by sensory deficits which are prevalent in elderly groups. Nevertheless, many unanswered questions remain about the possibility of accurately reflecting age related deficient performance. The presentation discusses relevant biases and methodological errors that make comparisons between ages difficult. Comparative data on the WAIS-IV GR scores and composite scores will be presented for two age groups: (a) 123 people aged 16 to 20 and (b) 158 subjects aged 75 to 90 years. The data stem from the Greek standardization sample which is representative of the general population in terms of gender, region and educational level. The results are discussed in terms of their importance for the understanding of the developmental changes in cognitive functionality and the need for further investigation.