Has there been a “massive” rise in IQ levels in the west? Evidence from Scottish children
Abstract
A ‘massive’ 18-point (1.2σ) increase in scores (from 1950 to 1980) has been reported on culture-reduced tests of IQ in fourteen of the world’s advanced economies. Here we examine the performance of representative samples of Scottish children in 1961 and 1983/4 on items from six scales of the Wechsler IQ test. We estimate that the rate of the gain in IQ for Scottish children over these 22.5 years did not exceed 2.5 IQ points (0.1 7 σ ) per generation. This result may diverge from the reported international trend because the ‘massive’ IQ-type gains found in other countries reflect the reliance of other investigators on multiple-choice, culture-reduced tests that tend to reward intelligent guessing and to penalise scrupulosity.
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The easier Vocabulary items are compatible with evolving patterns of word use in the language.
“compatible with the idea of evolving patterns of word use in the language (e.g.Brand, 1989).”
From No negative Flynn effect in France: Why variations of intelligence should not be assessed using tests based on cultural knowledge (2021) · cites this paper as Brand, 1989
Prior research has shown that some items in intelligence tests tend to become significantly easier or harder over time (item drifts).
“In line with this idea, prior research has shown that some items in intelligence tests tend to become significantly easier or harder over time (item drifts; e.g. Brand et al., 1989).”
From No negative Flynn effect in France: Why variations of intelligence should not be assessed using tests based on cultural knowledge (2021) · cites this paper as Brand et al., 1989
Flieller (1988) reached the same conclusion in a French dataset over three decades ago; Brand and colleagues (1989) also found a similar result of decreasing scores due to changes of item difficulty.
“As an example, Flieller (1988) reached the same conclusion in a French dataset over three decades ago; Brand and colleagues (1989) also found a similar result of decreasing scores due to changes of items difficulty”
From No negative Flynn effect in France: Why variations of intelligence should not be assessed using tests based on cultural knowledge (2021) · cites this paper as Brand et al., 1989
Cited by
Sorted by citations
One Century of Global IQ Gains: A Formal Meta-Analysis of the Flynn Effect (1909–2013)
Pietschnig, J., & Voracek, M. (2015) · Perspectives on Psychological Science · doi:10.1177/1745691615577701 · Cited by 316 · see citing works
Woodley, M. A., te Nijenhuis, J., Must, O., & Must, A. (2014) · Intelligence · doi:10.1016/j.intell.2013.12.004 · Cited by 46 · see citing works
Gonthier, C., Grégoire, J., & Besançon, M. (2021) · Intelligence · doi:10.1016/j.intell.2020.101512 · Cited by 20 · see citing works
- Authors
- Brand, C. R., Freshwater, S., & Dockrell, W. B.
- Affiliations
- University of Edinburgh (GB)
- Venue
- The Irish Journal of Psychology
- Publisher
- Informa UK Limited
- Published
- 1989-01
- Volume
- 10
- Issue
- 3
- Pages
- 388-393
- ISSN
- 0303-3910 (ISSN-L)
- 2158-0812
- OpenAlex
- W2060306630
- Cited by
- 35
- References
- 0
- Citations by year
- 2026: 1 · 2025: 1 · 2024: 1 · 2023: 1 · 2022: 1 · 2021: 1 · 2020: 1 · 2019: 1 · 2015: 3 · 2014: 1 · 2013: 4 · 2012: 3
- FWCI
- 0.94
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- The Irish Journal of Psychology (publishedVersion)
- Topics
- Social Sciences › Psychology › Experimental and Cognitive Psychology › Cognitive Abilities and Testing
- Social Sciences › Sociology and Political Science › Intergenerational and Educational Inequality Studies
- Social Sciences › Decision Sciences › Management Science and Operations Research › Psychometric Methodologies and Testing
- Keywords
- IQ gains, Flynn effect, Scottish children, multiple-choice tests, scrupulosity, test score trends
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