What the third edition changed
Fourteen subtests, two ways to add them up
Tap a subtest to see which IQ and which index it feeds. Some feed only one system, and one feeds neither. Then switch to adults aged 75 to 89, where the factors fall differently.9,3
FSIQ is shown as the combination of the Verbal and Performance IQ subtests. Sources disagree on whether Comprehension belongs to the Verbal Comprehension Index; this follows the sources that say it counts only toward the IQs.9,4
Norms to 89, and a structure that shifts with age
The upper age limit went from 75 to 89. The Verbal Comprehension and Working Memory indexes held steady across all ages. For adults over 75, though, the perceptual and speed factors loaded differently.3
The norm sample was 2,450 adults aged 16 to 89, with 200 per age group except the two oldest, which were smaller.2
The bridge edition
Our archive timeline links this entry to the web address "wais-ii". The correct address is used on this page and has been flagged for fixing in the timeline.
References
- [1]Development of the WAIS-III: a brief overview, history, and description. Graduate Journal of Counseling Psychology, Marquette University (PDF).epublications.marquette.edu
- [2]The Wechsler Adult Intelligence Scale (WAIS). SlideShare presentation.slideshare.net
- [3]Wechsler Adult Intelligence Scale: an overview. ScienceDirect Topics (Medicine and Dentistry).sciencedirect.com
- [4]Dissertation comparing the WAIS-IV with the WAIS-III. NSUWorks, Nova Southeastern University (PDF).nsuworks.nova.edu
- [5]Wechsler Adult Intelligence Scale. Psynso (2017).psynso.com
- [6]Wechsler Adult Intelligence Scale (WAIS). IQ Test Prep.iqtestprep.com
- [7]WAIS-IV: Wechsler Adult Intelligence Scale guide. Practice Test Geeks (2026).practicetestgeeks.com
- [8]Understanding the Wechsler scales: WAIS-III, WAIS-IV, and WISC-IV. Psychology Town (2026).psychology.town
- [9]Silva, M. A. Development of the WAIS-III. Graduate Journal of Counseling Psychology, Marquette University (PDF).marquette.edu
Related historical tests
The WAIS-R had three IQs and norms up to age 74. The WAIS-III added new subtests, four indexes and norms to age 89.
The original WAIS set up the verbal/performance split. The WAIS-III was the last adult edition to report it.
The children's Wechsler was moving to index scores too. Its third edition in 1991 added a processing-speed subtest and four indexes.
The WAIS-III was co-normed with the Wechsler Memory Scale. Verbal memory tests like the CVLT sit alongside it in neuropsychological batteries.
The WAIS-III Processing Speed Index uses timed symbol tasks, much as the d2 does, but as one part of an IQ battery.
The Woodcock-Johnson went fully factor-based. The WAIS-III took a step that way, adding factor-derived indexes but keeping the IQs.