"IQ scores have not been declining in developed countries since the 1990s."
Evidence9
A 2018 review reported that the United States sustained its historic IQ gain of about 0.3 points per year through 2014.
A 2018 review of international trends summarized U.S. evidence from multiple datasets.
It reports that the United States maintained its historic gain rate of about 0.3 IQ points per year through 2014, indicating continued increases rather than decline.
A 2018 review of international trends summarized U.S. evidence from multiple datasets.
It reports that the United States maintained its historic gain rate of about 0.3 IQ points per year through 2014, indicating continued increases rather than decline.
New UK norms for Raven's matrices showed fluid intelligence increased: 4-11-year-olds gained 8 IQ points from 1982-2007 and 7-15-year-olds gained 6.2 points from 1979-2008.
New UK standardizations of the Raven's Coloured and Standard Progressive Matrices were compared with earlier norms.
Children ages 4-11 gained about 8 IQ points from 1982 to 2007, and ages 7-15 gained about 6.2 points from 1979 to 2008, showing rising fluid-intelligence scores.
New UK standardizations of the Raven's Coloured and Standard Progressive Matrices were compared with earlier norms.
Children ages 4-11 gained about 8 IQ points from 1982 to 2007, and ages 7-15 gained about 6.2 points from 1979 to 2008, showing rising...
A 2020 reanalysis of French Wechsler data found that item bias created an illusory decline; after adjustment, ability increased from 1989-1999 and then stagnated from 1999-2009.
This reanalysis examined 111 common items across the French Wechsler Adult Intelligence Scale versions from 1989, 1999, and 2009, using norm samples totaling 2,979 people.
More than half the items became harder for later cohorts, which can create a false decline. After accounting for this bias, the authors report ability increased from 1989-1999 and then remained roughly flat from 1999-2009.
This reanalysis examined 111 common items across the French Wechsler Adult Intelligence Scale versions from 1989, 1999, and 2009, using norm samples totaling 2,979 people.
More than half the items became harder for later cohorts, which can create a false...
Austrian test-standardization data from 2005, 2011, and 2018 found positive IQ gains across all domains, with increases equivalent to about 0.21 to 0.91 standard deviations.
Austrian test-standardization data from 2005, 2011, and 2018 (1,392 residents ages 14-85) were analyzed across several cognitive domains.
Scores increased across all domains, with gains equivalent to about 0.21 to 0.91 standard deviations, indicating a positive Flynn effect from 2005 to 2018.
Austrian test-standardization data from 2005, 2011, and 2018 (1,392 residents ages 14-85) were analyzed across several cognitive domains.
Scores increased across all domains, with gains equivalent to about 0.21 to 0.91 standard deviations, indicating a...
A 2014 meta-analysis of modern Stanford-Binet and Wechsler comparisons since 1972 found an average gain of 2.93 IQ points per decade and no evidence the effect was diminishing.
A 2014 meta-analysis aggregated 53 modern Stanford-Binet and Wechsler comparisons since 1972, totaling 3,951 participants.
The average gain was 2.93 IQ points per decade, and the authors report this was not consistent with a diminishing or reversing trend.
A 2014 meta-analysis aggregated 53 modern Stanford-Binet and Wechsler comparisons since 1972, totaling 3,951 participants.
The average gain was 2.93 IQ points per decade, and the authors report this was not consistent with a diminishing or reversing trend.
A 2015 meta-analysis of 271 samples from 31 countries estimated continued annual gains of about 0.28 full-scale IQ points and 0.41 for fluid IQ across 1909-2013.
A 2015 meta-analysis compiled 271 samples totaling nearly 4 million people from 31 countries between 1909 and 2013.
It estimated annual gains of about 0.28 full-scale IQ points (0.41 for fluid IQ), showing continued increases even though gains slowed in recent decades.
A 2015 meta-analysis compiled 271 samples totaling nearly 4 million people from 31 countries between 1909 and 2013.
It estimated annual gains of about 0.28 full-scale IQ points (0.41 for fluid IQ), showing continued increases even though gains slowed in...
A 2023 meta-analysis of 1,038 Raven's Standard Progressive Matrices samples (299,155 people) from 1948-2020 found average gains of 2.2 IQ points per decade.
A 2023 meta-analysis examined 1,038 samples (299,155 people) on Raven's Standard Progressive Matrices from 1948 to 2020 across 72 countries.
The mean gain was about 2.2 IQ points per decade, indicating long-run upward trends rather than overall decline.
A 2023 meta-analysis examined 1,038 samples (299,155 people) on Raven's Standard Progressive Matrices from 1948 to 2020 across 72 countries.
The mean gain was about 2.2 IQ points per decade, indicating long-run upward trends rather than overall decline.
A 2007 analysis of U.S. Wechsler and Stanford-Binet norms reported post-1972 gains of about 0.305-0.311 IQ points per year, with a 3.8-4.6 point gain from 1989-2001.75.
A 2007 analysis compared 12 U.S. Wechsler and Stanford-Binet standardization samples from 1972 to 2002.
The post-1972 rate averaged about 0.305-0.311 IQ points per year, and the WISC-III to WISC-IV comparison implied roughly 3.8-4.6 points of gain from 1989 to 2001.75.
A 2007 analysis compared 12 U.S. Wechsler and Stanford-Binet standardization samples from 1972 to 2002.
The post-1972 rate averaged about 0.305-0.311 IQ points per year, and the WISC-III to WISC-IV comparison implied roughly 3.8-4.6 points of gain from 1989...
A U.S. adolescent study of 10,073 participants found no overall IQ decline from 1989-2003 and a positive gain of about 2.3 IQ points per decade at age 13.
A nationally representative U.S. adolescent sample (10,073 participants) took the Kaufman Brief Intelligence Test and was scored against 1989 and 2003 norms.
Across 1989-2003 there was no overall decline, and 13-year-olds showed a positive gain of about 2.3 IQ points per decade.
A nationally representative U.S. adolescent sample (10,073 participants) took the Kaufman Brief Intelligence Test and was scored against 1989 and 2003 norms.
Across 1989-2003 there was no overall decline, and 13-year-olds showed a positive gain of about 2.3...