The Wechsler Adult Intelligence Scale—Fourth Edition (WAIS-IV) is the world’s most widely used instrument for measuring the intellectual ability of older adolescents and adults (ages 16–90). Published in 2008 by Pearson, it replaced the traditional "Verbal" and "Performance" IQ scores with four specific index scores to provide a more detailed cognitive profile. Core Structure
- Verbal Comprehension (VCI) – Measures verbal reasoning, knowledge, and concept formation (e.g., vocabulary, similarities between objects/concepts).
- Perceptual Reasoning (PRI) – Assesses non‑verbal and fluid reasoning, visual-motor integration, and spatial processing (e.g., block design, matrix reasoning).
- Working Memory (WMI) – Evaluates attention, concentration, and mental manipulation of information (e.g., digit span, arithmetic).
- Processing Speed (PSI) – Measures visual scanning, graphomotor speed, and rapid decision‑making (e.g., symbol search, coding).
Time: Usually takes between 60 and 90 minutes for the core subtests.
The results are synthesized into a Full Scale IQ (FSIQ), which represents overall intellectual ability.
The Future: WAIS-V
As of 2025, Pearson is actively developing the WAIS-V. Based on recent research, expect the WAIS-V to include:
