The DOI matches its Crossref record; 268 of the 268 references it cites were found in a registry or an index; none of the 34 sources its claims cite is checked for support yet.
The Flynn effect: A meta-analysis.
Open accessAbstract
The Flynn effect refers to the observed rise in IQ scores over time, which results in norms obsolescence. Although the Flynn effect is widely accepted, most efforts to estimate it have relied upon "scorecard" approaches that make estimates of its magnitude and error of measurement controversial and prevent determination of factors that moderate the Flynn effect across different IQ tests. We conducted a meta-analysis to determine the magnitude of the Flynn effect with a higher degree of precision, to determine the error of measurement, and to assess the impact of several moderator variables on the mean effect size. Across 285 studies (N = 14,031) since 1951 with administrations of 2 intelligence tests with different normative bases, the meta-analytic mean was 2.31, 95% CI [1.99, 2.64], standard score points per decade. The mean effect size for 53 comparisons (N = 3,951, excluding 3 atypical studies that inflate the estimates) involving modern (since 1972) Stanford-Binet and Wechsler IQ tests (2.93, 95% CI [2.3, 3.5], IQ points per decade) was comparable to previous estimates of about 3 points per decade but was not consistent with the hypothesis that the Flynn effect is diminishing. For modern tests, study sample (larger increases for validation research samples vs. test standardization samples) and order of administration explained unique variance in the Flynn effect, but age and ability level were not significant moderators. These results supported previous estimates of the Flynn effect and its robustness across different age groups, measures, samples, and levels of performance.
Overview
Integrity signals
Registry
Cites
Statistics
Verification
Claims the paper makes
0 of 34 cited sources checked · 0 supported · 0 flagged
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“but age and ability level were not significant moderators.”
§ The Flynn Effect: A Meta-analysis > Abstract
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“larger increases for validation research samples vs. test standardization samples”
§ The Flynn Effect: A Meta-analysis > Abstract
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The mean effect (k = 12, n = 925) for the modern tests other than Wechsler and Binet pairs normed since 1972 in the random effects model was 0.30 IQ points per year, 95% CI [0.21, 0.40], z = 6.13, p < .0001.”
§ The Flynn Effect: A Meta-analysis > Results > Further Analysis within Test Groups
Tests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Across 285 studies (N = 14,031) since 1951 with administrations of two intelligence tests with different normative bases, the meta-analytic mean was 2.31, 95% CI [1.99, 2.64], standard score points per decade.”
§ The Flynn Effect: A Meta-analysis > Abstract
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesThe paper states this without a source or data behind it here, so there is nothing to check it against. The quote shows it is in the paper.
In the paper
“Eighty-two percent of the distribution of true effects was above zero.”
§ The Flynn Effect: A Meta-analysis > Results > Overall Model
Strength:plain· not yet calibratedn = 14,031Tests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The effects were significantly heterogeneous, (Q(284) = 4710, p < .0001).”
§ The Flynn Effect: A Meta-analysis > Results > Overall Model
Load-bearingStrength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Although each group mean effect was significantly different from zero (Table 2), type of sample was not significant in the random effects analysis, Q(1) = 3.14, p < .076.”
§ The Flynn Effect: A Meta-analysis > Results > Moderator Analyses of the Modern Tests
Strength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Inspection of Figure 2 revealed an unusual bimodal pattern in the effects representing samples with the lowest ability.”
§ The Flynn Effect: A Meta-analysis > Results > Moderator Analyses of the Modern Tests
Load-bearingStrength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The estimated I2, or proportion of the total variance due to true study variance, was I2 = 0.94.”
§ The Flynn Effect: A Meta-analysis > Results > Overall Model
Strength:plain· not yet calibratedn = 14,031Tests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesA result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The mean effect (k = 14, n = 557) in the random effects model involving the McCarthy was 0.33 IQ points per year, 95% CI [0.15, 0.51], z = 3.60, p < .0001.”
§ The Flynn Effect: A Meta-analysis > Results > Further Analysis within Test Groups
Tests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passes
- It may state two separate claims as one. 42
- Probably not a substantial claim. 35
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The Tau, or estimated standard deviation of the true effects, was τ = 0.25, resulting in a credibility interval of −0.26 to +0.72.”
§ The Flynn Effect: A Meta-analysis > Results > Overall Model
Strength:plain· not yet calibratedn = 14,031Tests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesIt may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The significant mixed effects meta-regression slope of effect size on ability level was b = −.01, 95% CI [−.016, −.004), z = −3.37, p < .0007. The Q for the model in this analysis was 11.38, accounting for 15.8% of the total variability as estimated by the Unrestricted Likelihood method.”
§ The Flynn Effect: A Meta-analysis > Results > Moderator Analyses of the Modern Tests
Strength:hedged· not yet calibratedCausal:correlational· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesIt may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The regression of effect size on age was nonsignificant, accounting for less than one percent of the variance in effect sizes.”
§ The Flynn Effect: A Meta-analysis > Results > Moderator Analyses of the Modern Tests
Strength:plain· not yet calibratedn = 3,951Tests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesIt may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Eliminating the three lowest ability effects results in a mean estimate of the remaining 53 effects (n = 3,951) of 0.293 points per year, 95% CI [0.23, 0.35], and the regression of effect on ability is no longer significant.”
§ The Flynn Effect: A Meta-analysis > Results > Moderator Analyses of the Modern Tests
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesIt may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“There is no apparent publication bias, which would be represented by a gap on the lower left side of the plot. A similar absence of a gap is seen on the lower right side of the plot.”
§ The Flynn Effect: A Meta-analysis > Results > Distribution of Effects
Strength:hedged· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesIt may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The mean effect over 285 total studies (n = 14,031) in the random effects model was 0.231 IQ points per year, 95% CI [0.20, 0.26], z = 14.10, p < .0001, with a confidence interval and p-value indicating that the Flynn effect is different from zero1.”
§ The Flynn Effect: A Meta-analysis > Results > Overall Model
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesIt may state two separate claims as one.
- Rests on an assumption: The 27 multifactorial tests chosen represent the major IQ tests in use over the past few decades.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“There was a significant between-test group effect, Q(5) = 231, p < .0001, with test group explaining 5.2% of the explainable variance in effects.”
§ The Flynn Effect: A Meta-analysis > Results > Moderator Analysis
Strength:plain· not yet calibratedCausal:correlational· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesIt may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The mean effect (k = 17, n = 1,325) in the random effects model was 0.02 IQ points per year, 95% CI [−0.15, 0.19], z = 0.21, p < .84.”
§ The Flynn Effect: A Meta-analysis > Results > Further Analysis within Test Groups
Strength:plain· not yet calibratedn = 1,325Tests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesIt may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The mean effect (k = 34, n = 1,611) in the random effects model was 0.02 IQ points per year, 95% CI [−0.16, 0.19], z = 0.19, p = .85.”
§ The Flynn Effect: A Meta-analysis > Results > Further Analysis within Test Groups
Strength:plain· not yet calibratedn = 1,611Tests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesIt may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The intercept was significant (a = 0.38, z = 2.58, p < .01), but the slope was not (b = −.002, z = −1.08, p < .28), indicating that the effect did not change significantly over the range of ability levels represented in this set of effects.”
§ The Flynn Effect: A Meta-analysis > Results > Moderator Analysis
Strength:hedged· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesIt may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Tests were frequently counterbalanced so that approximately half of the sample got each test first. However, in a substantial number of the studies, one test was uniformly given first.”
§ The Flynn Effect: A Meta-analysis > Method > Moderator Analyses
Strength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The mean effects for the counterbalanced group (k = 30, n = 2,912) (M = 0.29, 95% CI [0.23, 0.36]) and the group of effects where the old test was given second (k = 8, n = 505) (M = 0.54, 95% CI [0.16, 0.91]) were significantly different from zero.”
§ The Flynn Effect: A Meta-analysis > Results > Moderator Analyses of the Modern Tests
Strength:plain· not yet calibratedn = 2,912Tests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesIt may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The results show that the IQ increase is pervasive, not only with respect to geography and time, but also with respect to the tests used to measure IQ.”
§ The Flynn Effect: A Meta-analysis > Discussion > Limitations
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesIt may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“and the standard error of this estimate is 0.35 (resulting in a 95% CI that extends about .7, rounded to 1 point, on either side of 3 points per decade).”
§ The Flynn Effect: A Meta-analysis > Discussion > Conclusions
Strength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesIt may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Examining just the modern tests administered in a counterbalanced order and excluding the three atypical studies showed that the estimates for pairings of Wechsler/Wechsler, Binet/Binet, and Wechsler/Binet tests (all about 0.29) were remarkably similar to the overall estimate of 0.293 per year.”
§ The Flynn Effect: A Meta-analysis > Discussion > Moderator Analyses
Strength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesIt may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“when only the modern Wechsler/Binet tests were considered in isolation, the magnitude of the effect appears to be close to 3 points per decade and showed no evidence of reducing in magnitude.”
§ The Flynn Effect: A Meta-analysis > Discussion > Implications of the Flynn Effect for Theory and Practice
Load-bearingStrength:hedged· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesIt may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“For the overall analyses and within the test groups, mean effects differed by no more than 0.03 points per year. All significance tests and tests of heterogeneity resulted in the same conclusions reached above.”
§ The Flynn Effect: A Meta-analysis > Results > Sensitivity Analysis
Strength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesIt may state two separate claims as one.
The paper states this without a source or data behind it here, so there is nothing to check it against. The quote shows it is in the paper.
In the paper
“However, if the new test was given first, the estimate (0.54) was larger”
§ The Flynn Effect: A Meta-analysis > Discussion > Moderator Analyses
Strength:plain· not yet calibratedCausal:correlational· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesIt may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Our support for a robust Flynn effect, manifested across various tests in nearly 300 studies”
§ The Flynn Effect: A Meta-analysis > Discussion > Implications of the Flynn Effect for Theory and Practice
Load-bearingStrength:boosted· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesIt may state two separate claims as one.
The paper states this without a source or data behind it here, so there is nothing to check it against. The quote shows it is in the paper.
In the paper
“If the old test was given first, the estimate (0.14) was smaller”
§ The Flynn Effect: A Meta-analysis > Discussion > Moderator Analyses
Strength:plain· not yet calibratedCausal:correlational· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesIt may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The present findings, which demonstrate the pervasiveness and stability of the Flynn effect across multiple tests and many decades”
§ The Flynn Effect: A Meta-analysis > Discussion > Implications of the Flynn Effect for Theory and Practice
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesIt may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The lowest possible score on the SB-4 is 36, and the lowest possible score on the WAIS-R is 45. Individuals who obtain the lowest possible score on both tests will still have an apparent difference in their standard scores of 9 points. Consistent with the plot, as the scores get closer to the mean of 100, the differences in the scales become smaller, and the effects become smaller.”
§ The Flynn Effect: A Meta-analysis > Results > Moderator Analyses of the Modern Tests
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesIt may state two separate claims as one.
In the paper
“The Flynn effect is less well known and often not taught in behavioral science training programs (Hagen, Drogin, & Guilmette, 2008).”
§ The Flynn Effect: A Meta-analysis > Historical Background
What the sources say
- Not matchedcites Hagen, Drogin, & Guilmette, 2008
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Strength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
- Not matched
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“These estimates ranged from 90.5–99.1% per block, with an average agreement of 95.8% per block.”
§ The Flynn Effect: A Meta-analysis > Method > Coding Procedures
Strength:plain· not yet calibratedn = 2Tests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“These results supported previous estimates of the Flynn effect and its robustness across different age groups, measures, samples, and levels of performance.”
§ The Flynn Effect: A Meta-analysis > Abstract
Load-bearingStrength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesIt may state two separate claims as one.
None of the sources cited for this claim could be matched to a paper in Crossref, so there is nothing to check it against.
In the paper
“Further, there is considerable contention over factors that may cause the Flynn effect (Flynn, 2007, 2012; Neisser, 1998).”
§ The Flynn Effect: A Meta-analysis > Flynn’s Work
What the sources say
- Not matchedcites Flynn, 2007, 2012
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites Neisser, 1998
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Strength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it.
- Not matched
None of the sources cited for this claim could be matched to a paper in Crossref, so there is nothing to check it against.
In the paper
“More recently, the Flynn effect was supported by calculations of IQ score gains between 1972 and 2006 for different normative versions of the Stanford-Binet (SB), Wechsler Adult Intelligence Scale (WAIS), and Wechsler Intelligence Scale for Children (WISC) (Flynn, 2009a). The average increase in IQ scores per year was 0.31, which was consistent with Flynn’s (1984a) earlier findings.”
§ The Flynn Effect: A Meta-analysis > Historical Background
What the sources say
- Not matchedcites Flynn, 2009a
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites Flynn, 1984a
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Strength:plain· not yet calibratedCausal:correlational· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesIt may state two separate claims as one.
- Not matched
In the paper
“Recent evidence has suggested that middle and lower ability groups (IQ = 79–109) demonstrate the customary 0.31–0.37-point increase per year, whereas higher ability groups (IQ = 110+) demonstrate a minimal increase of 0.06–0.15 points per year (Zhou, Zhu, Weiss, & Pearson, 2010).”
§ The Flynn Effect: A Meta-analysis > The Current Study
What the sources say
- Not matchedcites Zhou, Zhu, Weiss, & Pearson, 2010
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Strength:hedged· not yet calibratedCausal:correlational· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it.
- Not matched
In the paper
“Recent evidence has suggested that middle and lower ability groups (IQ = 79–109) demonstrate the customary 0.31–0.37-point increase per year, whereas higher ability groups (IQ = 110+) demonstrate a minimal increase of 0.06–0.15 points per year (Zhou, Zhu, Weiss, & Pearson, 2010).”
§ The Flynn Effect: A Meta-analysis > The Current Study
What the sources say
- Not matchedcites Zhou, Zhu, Weiss, & Pearson, 2010
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Strength:hedged· not yet calibratedCausal:correlational· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it.
- Not matched
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“We did not expect to find evidence for publication bias in this meta-analysis. The descriptive data collected from each study in the form of sample sizes, means, and correlations between tests is not typically the type of data that is subject to tests of significance and thus would not be a direct cause of failure to publish due to non-significance. Additionally, many of the effects were gleaned”
§ The Flynn Effect: A Meta-analysis > Method > Statistical Methods
Strength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
- The authors state this as an assumption: The results of test validation studies provide important information irrespective of the findings and would therefore constitute publishable data.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“This pattern indicates that some of the lower ability samples had higher than average Flynn effects whereas others had lower than average Flynn effects.”
§ The Flynn Effect: A Meta-analysis > Results > Moderator Analyses of the Modern Tests
Strength:hedged· not yet calibratedCausal:correlational· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesIt may state two separate claims as one.
In the paper
“Flynn’s study revealed a 13.8-point increase in IQ scores between 1932 and 1978, amounting to a 0.3-point increase per year, or approximately 3 points per decade.”
§ The Flynn Effect: A Meta-analysis > Historical Background
What the sources say
- Not matchedcites Flynn (1984a)
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Strength:plain· not yet calibratedCausal:correlational· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesIt may state two separate claims as one.
- Not matched
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Unawareness of the Flynn effect on the part of test examiners can compound this problem.”
§ The Flynn Effect: A Meta-analysis > Discussion > Implications of the Flynn Effect for Theory and Practice
Strength:plain· not yet calibratedCausal:conditional· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it.
In the paper
“Our finding that the Flynn effect has not diminished over time and may be larger for modern than older tests is not consistent with Sundet et al.’s (2008) hypothesis relating increasing IQ scores and decreasing family size”
§ The Flynn Effect: A Meta-analysis > Discussion > Implications of the Flynn Effect for Theory and Practice
What the sources say
- Not matchedcites Sundet et al.’s (2008)
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Load-bearingStrength:hedged· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesIt may state two separate claims as one.
- Not matched
In the paper
“This finding is consistent with previous research (Flynn, 1984, 1987).”
§ The Flynn Effect: A Meta-analysis > Discussion > Moderator Analyses
What the sources say
- Not matchedcites Flynn, 1984, 1987
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Strength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it.
- Not matched
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“This child may be more likely to receive a diagnosis of a learning disability during this second assessment than a recommendation of special education services.”
§ The Flynn Effect: A Meta-analysis > Discussion > Implications of the Flynn Effect for Theory and Practice
Strength:hedged· not yet calibratedCausal:conditional· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✗ Based: failsProbably not a substantial claim. The paper’s conclusions may not depend on it. The paper may give no reason why it holds.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Given the variety of subtests underlying the IQ scores included in our meta-analyses, and the convergence of Flynn effect estimates around 0.29 for the modern tests, the order effect tends to be transitive with a mean magnitude of approximately ± .20.”
§ The Flynn Effect: A Meta-analysis > Discussion > Moderator Analyses
Strength:hedged· not yet calibratedCausal:correlational· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesIt may state two separate claims as one.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“However, the number of comparisons included in this review appears more than sufficient to assess the magnitude of the Flynn effect and the precision of the obtained value, and to address the additional research questions under consideration.”
§ The Flynn Effect: A Meta-analysis > Discussion > Limitations
Strength:hedged· not yet calibratedTests✓ Asserted: passes✗ Checkable: fails✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. It may be too vague to check against evidence. The paper’s conclusions may not depend on it. It may state two separate claims as one.
None of the sources cited for this claim have been checked yet.
In the paper
“Several recent studies indicate that the Flynn effect is not limited to intelligence tests but may be measured in tests of memory (Baxendale, 2010; Rönnlund & Nilsson, 2008, 2009) and object naming (Connor, Spiro, Obler, & Martin, 2004), as well as certain commonly used neuropsychological tests (Dickinson & Hiscock, 2011).”
§ The Flynn Effect: A Meta-analysis > Discussion > Implications of the Flynn Effect for Theory and Practice
What the sources say
Strength:hedged· not yet calibratedCausal:correlational· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Results revealed no difference in the Flynn effect based on participant age, suggesting that the Flynn effect is consistent across age cohorts.”
§ The Flynn Effect: A Meta-analysis > Discussion > Moderator Analyses
Load-bearingStrength:hedged· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesIt may state two separate claims as one.
None of the sources cited for this claim have been checked yet.
In the paper
“The overall Flynn effect of 2.31 produced by this meta-analysis was lower than Flynn’s (2009a) value of 3.11 and Fletcher et al.’s (2010) value of 2.80. It also fell below Dickinson and Hiscock’s (2010) estimate of 2.60, which was the average of separate calculations for each of the 11 Wechsler subtests.”
§ The Flynn Effect: A Meta-analysis > Discussion > Major Findings
What the sources say
Strength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesIt may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“These findings suggest that the mean magnitude of the Flynn effect may not change significantly with level of ability and that the correction can be applied to scores across the spectrum of ability level.”
§ The Flynn Effect: A Meta-analysis > Discussion > Moderator Analyses
Load-bearingStrength:hedged· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesIt may state two separate claims as one.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“We did not address this issue in this metaanalysis”
§ The Flynn Effect: A Meta-analysis > Discussion > Implications of the Flynn Effect for Theory and Practice
Load-bearingStrength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesProbably not a substantial claim.
In the paper
“The larger effect for modern than older tests could be regarded as consistent with Lynn’s (2009) hypothesis pertaining to pre- and early postnatal nutrition.”
§ The Flynn Effect: A Meta-analysis > Discussion > Implications of the Flynn Effect for Theory and Practice
What the sources say
- Not matchedcites Lynn’s (2009)
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
Strength:hedged· not yet calibratedCausal:correlational· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it.
- Not matched
In the paper
“Our data do not address Kaufman’s (2010) more specific concern about asymmetric order effects such that taking the newer test first increased subsequent performance on the older test more than taking the older test first increases subsequent performance on the newer test.”
§ The Flynn Effect: A Meta-analysis > Discussion > Moderator Analyses
What the sources say
- Not checked — no full text of the sourcecites Kaufman (2010) source
Strength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Moreover, the exact size of the Flynn effect may vary from one sample to another.”
§ The Flynn Effect: A Meta-analysis > Discussion > Implications of the Flynn Effect for Theory and Practice
Strength:hedged· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✗ Based: failsProbably not a substantial claim. The paper’s conclusions may not depend on it. The paper may give no reason why it holds.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“there may be significant order effects”
§ The Flynn Effect: A Meta-analysis > Discussion > Limitations
Strength:hedged· not yet calibratedCausal:conditional· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✗ Based: failsProbably not a substantial claim. The paper’s conclusions may not depend on it. The paper may give no reason why it holds.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Additionally, the large number of studies included in our meta-analysis provides a strong empirical basis for concluding that comparable IQ increases are evident in samples ranging from preschool children to elderly adults.”
§ The Flynn Effect: A Meta-analysis > Discussion > Limitations
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesIt may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The data available from tests other than IQ tests are not likely to be sufficient in quality or quantity to yield precise Flynn effect estimates”
§ The Flynn Effect: A Meta-analysis > Discussion > Implications of the Flynn Effect for Theory and Practice
Load-bearingStrength:hedged· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesProbably not a substantial claim.
The paper states this without a source or data behind it here, so there is nothing to check it against. The quote shows it is in the paper.
In the paper
“The usefulness of a meta-analysis depends to a great extent on the accessibility of studies meeting inclusion criteria.”
§ The Flynn Effect: A Meta-analysis > Discussion > Limitations
Strength:plain· not yet calibratedCausal:correlational· not yet calibratedTests✓ Asserted: passes✗ Checkable: fails✗ Load-bearing: fails✗ Based: failsProbably not a substantial claim. It may be too vague to check against evidence. The paper’s conclusions may not depend on it. The paper may give no reason why it holds.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“the data collected from Scandinavian young men, most of whom are evaluated for suitability for the armed services, are more representative of the Scandinavian population than potential conscripts in the United States who self-select into the armed services are of the American population.”
§ The Flynn Effect: A Meta-analysis > Discussion > Limitations
Strength:plain· not yet calibratedCausal:correlational· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✗ Based: failsProbably not a substantial claim. The paper’s conclusions may not depend on it. The paper may give no reason why it holds.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“However, in capital punishment cases, life and death may reside on a 3-point difference of 76 versus 73, or 71 versus 68.”
§ The Flynn Effect: A Meta-analysis > Discussion > Conclusions
Tests✓ Asserted: passes✓ Checkable: passes✓ Load-bearing: passes✓ Based: passesProbably not a substantial claim.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“On the other hand, our method has the advantage of being applicable to a very large number of informative samples.”
§ The Flynn Effect: A Meta-analysis > Discussion > Limitations
Load-bearingStrength:plain· not yet calibratedTests✓ Asserted: passes✗ Checkable: fails✓ Load-bearing: passes✓ Based: passesProbably not a substantial claim. It may be too vague to check against evidence.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“For the study of a cohort phenomenon like the Flynn effect, this approach is appropriate.”
§ The Flynn Effect: A Meta-analysis > Discussion > Limitations
Strength:plain· not yet calibratedTests✓ Asserted: passes✗ Checkable: fails✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. It may be too vague to check against evidence. The paper’s conclusions may not depend on it.
- Rests on an assumption: The Flynn effect is a cohort phenomenon.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“Further, there was no dearth of effect sizes at the lower end of the distribution of effect sizes (Figure 1), which suggests there was no oversampling of studies producing higher Flynn effects.”
§ The Flynn Effect: A Meta-analysis > Discussion > Limitations
Strength:hedged· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes? Load-bearing: unclear✓ Based: passesIt may state two separate claims as one.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“Our method is not as direct as Flynn’s tracking of raw scores on Raven’s Matrices, nor does it provide the detailed information that can be obtained by comparing old and new versions of the Wechsler and Stanford-Binet batteries in the same individuals.”
§ The Flynn Effect: A Meta-analysis > Discussion > Limitations
Strength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
The paper states this without a source or data behind it here, so there is nothing to check it against. The quote shows it is in the paper.
In the paper
“For example, mean values can be greatly influenced by the number and magnitude of extreme values such that the resulting value may not be an adequate measure of central tendency nor an effective illustration of the relation between IQ score and the moderators assessed.”
§ The Flynn Effect: A Meta-analysis > Discussion > Limitations
Strength:plain· not yet calibratedCausal:conditional· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“but precise estimates for IQ tests will provide a reliable standard against which data from other tests can be evaluated.”
§ The Flynn Effect: A Meta-analysis > Discussion > Implications of the Flynn Effect for Theory and Practice
Tests✓ Asserted: passes✗ Checkable: fails✓ Load-bearing: passes✗ Based: failsProbably not a substantial claim. It may be too vague to check against evidence. The paper may give no reason why it holds.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“A precise correction, however, cannot be assured in all circumstances because the Flynn effect, as it applies to a given test, may strengthen or weaken at any time in the future.”
§ The Flynn Effect: A Meta-analysis > Discussion > Implications of the Flynn Effect for Theory and Practice
Strength:hedged· not yet calibratedCausal:conditional· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it.
The paper states this without a source or data behind it here, so there is nothing to check it against. The quote shows it is in the paper.
In the paper
“Relying on one numerical value to represent a continuous variable, including IQ score and age, results in a significant loss of information.”
§ The Flynn Effect: A Meta-analysis > Discussion > Limitations
Strength:plain· not yet calibratedCausal:direct· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“many tests are never re-normed and therefore lie beyond the reach of this method”
§ The Flynn Effect: A Meta-analysis > Discussion > Limitations
Strength:plain· not yet calibratedCausal:direct· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“Although a thorough review was conducted on PsycINFO® and in test manuals, possibly there were studies meeting inclusion criteria that were not accessed.”
§ The Flynn Effect: A Meta-analysis > Discussion > Limitations
Strength:hedged· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“These findings are consistent with previous research”
§ The Flynn Effect: A Meta-analysis > Discussion > Conclusions
Strength:plain· not yet calibratedTests✓ Asserted: passes✗ Checkable: fails✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. It may be too vague to check against evidence. The paper’s conclusions may not depend on it.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“In this case, the IQ score produced by the second assessment may be particularly inflated due to both the Flynn effect and prior exposure.”
§ The Flynn Effect: A Meta-analysis > Discussion > Implications of the Flynn Effect for Theory and Practice
Strength:hedged· not yet calibratedCausal:conditional· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“In addition, validation studies rely on group-level data and presuppose a representative normative basis for the derivation of a standardized IQ score.”
§ The Flynn Effect: A Meta-analysis > Discussion > Limitations
Strength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✗ Based: failsProbably not a substantial claim. The paper’s conclusions may not depend on it. The paper may give no reason why it holds. It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“and with the argument that it is feasible and advisable to correct IQ scores for the Flynn effect in high stakes decisions.”
§ The Flynn Effect: A Meta-analysis > Discussion > Conclusions
Load-bearingStrength:plain· not yet calibratedTests✓ Asserted: passes✗ Checkable: fails✓ Load-bearing: passes✓ Based: passesProbably not a substantial claim. It may be too vague to check against evidence. It may state two separate claims as one.
What the paper did — it cites no source for this, so there is none to check. The quote shows it is in the paper.
In the paper
“direct within-examinee comparisons have not been made for many tests even if the tests have been re-normed.”
§ The Flynn Effect: A Meta-analysis > Discussion > Limitations
Strength:plain· not yet calibratedTests✓ Asserted: passes✓ Checkable: passes✗ Load-bearing: fails✓ Based: passesProbably not a substantial claim. The paper’s conclusions may not depend on it.
The paper relies on this without support.
Research on the Flynn effect has focused almost exclusively on the effect produced from administrations of the Stanford-Binet and Wechsler tests.
“Research on the Flynn effect has focused almost exclusively on the effect produced from administrations of the Stanford-Binet and Wechsler tests.”
The paper relies on this without support.
Validation studies conducted by test publishers likely employed the most rigorous procedures with regard to sampling, selection of administrators, and adherence to administration and scoring protocols.
“Validation studies conducted by test publishers likely employed the most rigorous procedures with regard to sampling, selection of administrators, and adherence to administration and scoring protocols.”
The paper relies on this without support.
The 27 multifactorial tests chosen represent the major IQ tests in use over the past few decades.
“There may be other multifactorial tests to consider, but the 27 we chose represent the major IQ tests in use over the past few decades.”
The authors state this as an assumption.
The results of test validation studies provide important information irrespective of the findings and would therefore constitute publishable data.
“A formal search for unpublished studies was not undertaken; it was presumed that the results of test validation studies would provide important information irrespective of the findings and would therefore constitute publishable data.”
The paper relies on this without support.
The greater impact of the Flynn effect on fluid versus crystallized intelligence is well-established.
“because the greater impact of the Flynn effect on fluid versus crystallized intelligence is well-established.”
The paper relies on this without support.
The Flynn effect is a cohort phenomenon.
“For the study of a cohort phenomenon like the Flynn effect, this approach is appropriate.”
The paper relies on this without support.
The convention in society is to use a cut point of 70 for intellectual disability.
“Because the convention in our society is to use a cut point of 70”
The paper relies on this without support.
No comparable data exist for American young men.
“Unfortunately, no comparable data exist for American young men.”
The paper relies on this without support.
The Raven’s test administered to Scandinavian young men has not changed in format or content since its development.
“Whereas the Raven’s test administered to Scandinavian young men has not changed in format or content since its development”
The paper relies on this without support.
The Armed Services Vocational Aptitude Battery administered to potential conscripts in the United States has changed in format or content.
“this is not the case for the Armed Services Vocational Aptitude Battery”
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
The source backs part of the claim, not all of it — or backs it for a different population, condition or comparison.
In the citing paper
“with the United States reporting a growth of 3 IQ points every ten years, a pattern that has been constant for about a century (Flynn 1984, 1987, 2007; Pietschnig and Voracek 2015; Trahan et al. 2014)”
From Wait, Where’s the Flynn Effect on the WAIS-5? (2024) · cites this paper as Trahan et al. 2014
Experimental — accuracy not yet measuredThe source backs part of the claim, not all of it — or backs it for a different population, condition or comparison.
In the citing paper
“Two large meta-analyses have found that the Flynn effect amounted to about three IQ points per decade during the past century [4, 5].”
From The secular trend of intelligence test scores: The Danish experience for young men born between 1940 and 2000 (2021) · cites this paper as [5]
Experimental — accuracy not yet measuredThe source backs part of the claim, not all of it — or backs it for a different population, condition or comparison.
In the citing paper
“Both meta-analyses listed a small number of studies reporting negative Flynn effects, which suggests that observed intelligence decreases can reflect fluctuations around a stable or increasing average (see Pietschnig & Voracek, 2015, Figure 2;Trahan et al., 2014, Figure 2), due either to chance or to methodological bias.”
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 Trahan et al., 2014
Experimental — accuracy not yet measuredThe cited source says what the claim attributes to it.
In the citing paper
“strikingly lower than the 3 points per decade identified from meta-analyses (Pietschnig and Voracek 2015; Trahan et al. 2014) and sanctioned as an adjustment to be made for Wechsler FSIQs in ID diagnosis by AAIDD (Schalock et al. 2021), especially in capital punishment court cases.”
From Wait, Where’s the Flynn Effect on the WAIS-5? (2024) · cites this paper as Trahan et al. 2014
The cited source says what the claim attributes to it.
In the citing paper
“On the other hand, recent large meta-analyses have substantially disagreed on this matter: one meta-analysis found that the Flynn effect has slowed but not halted (Pietschnig & Voracek, 2015; including 4 million subjects in 31 countries), and another concluded that the Flynn effect continues at the same rate (Trahan et al., 2014; including 14.000 subjects in 285 studies).”
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 Trahan et al., 2014
The check wasn’t confident either way, so it gives no verdict — never disputed.
In the citing paper
“One example of how increased capacity is associated with a proxy measure of reserve is the aforementioned effect of education on synaptic density.50”
From Maintenance, reserve and compensation: the cognitive neuroscience of healthy ageing (2018) · cites this paper as [50]
Experimental — accuracy not yet measuredThe check wasn’t confident either way, so it gives no verdict — never disputed.
In the citing paper
“A good example of a factor that promotes reserve is education, which improves neural resources during childhood and young adulthood, possibly by enhancing synaptic density 50”
From Maintenance, reserve and compensation: the cognitive neuroscience of healthy ageing (2018) · cites this paper as [50]
Experimental — accuracy not yet measured
Statistics that don’t add up
Each reported p-value recomputed from its test statistic and degrees of freedom.
Inconsistent p-value: z = 3.60, p < .0001
MinorThe paper reports p < .0001 here; recomputing from the test statistic and its degrees of freedom gives p < .001 (two-tailed). The check cannot tell whether the statistic or the p-value is the misprint.
Reported p < .0001 · recomputed p < .001
“z = 3.60, p < .0001”
p-value fits an unstated one-tailed test: z = −3.37, p < .0007
MinorThe paper reports p < .0007 here; recomputing from the test statistic and its degrees of freedom gives p < .001 (two-tailed). The reported value is what a one-tailed test gives, but the paper does not say near this result that a one-tailed test was used.
Reported p < .0007 · recomputed p < .001
“z = −3.37, p < .0007”
Statistics recomputed
Every reported test result, recomputed from its test statistic and degrees of freedom. A result shows as not adding up only once an independent check has confirmed it.
- Doesn’t add upz = 3.6reported p < .0001 · recomputed p < .001
“z = 3.60, p < .0001”
- Doesn’t add upz = -3.37reported p < .0007 · recomputed p < .001
“z = −3.37, p < .0007”
- Not confirmedQ(1) = 3.14reported p < .076 · recomputed p = .076
“Q(1) = 3.14, p < .076”
- Consistentz = 14.1reported p < .0001 · recomputed p < .001
“z = 14.10, p < .0001”
- ConsistentQ(284) = 4710reported p < .0001 · recomputed p < .001
“Q(284) = 4710, p < .0001”
- ConsistentQ(5) = 231reported p < .0001 · recomputed p < .001
“Q(5) = 231, p < .0001”
- Consistentz = 2.58reported p < .01 · recomputed p = .010
“z = 2.58, p < .01”
- Consistentz = -1.08reported p < .28 · recomputed p = .280
“z = −1.08, p < .28”
- Consistentz = 11.12reported p < .0001 · recomputed p < .001
“z =11.12, p < .0001”
- ConsistentQ(151) = 3237reported p < .0001 · recomputed p < .001
“Q(151) = 3237, p < .0001”
- Consistentz = 0.21reported p < .84 · recomputed p = .834
“z = 0.21, p < .84”
- ConsistentQ(16) = 232reported p < .0001 · recomputed p < .001
“Q(16) = 232, p < .0001”
- Consistentz = 0.19reported p = .85 · recomputed p = .849
“z = 0.19, p = .85”
- ConsistentQ(33) = 295reported p < .0001 · recomputed p < .001
“Q(33) = 295, p < .0001”
- Consistentz = 6.13reported p < .0001 · recomputed p < .001
“z = 6.13, p < .0001”
- ConsistentQ(11) = 44reported p < .0001 · recomputed p < .001
“Q(11) = 44, p < .0001”
- ConsistentQ(13) = 74reported p < .0001 · recomputed p < .001
“Q(13) = 74, p < .0001”
- Consistentz = 10.06reported p < .00001 · recomputed p < .001
“z = 10.06, p < .00001”
- ConsistentQ(55) = 597.34reported p < .0001 · recomputed p < .001
“Q(55) = 597.34, p < .0001”
- Consistentz = 16.83reported p < .0001 · recomputed p < .001
“z = 16.83, p < .0001”
- ConsistentQ(377) = 5581reported p < .0001 · recomputed p < .001
“Q(377) = 5581, p < .0001”
Self-check
Percentages, sums and reported differences re-computed from the paper’s own numbers.
Each contradiction between two passages listed here was confirmed by an independent check.
Forty-year WISC-R example applies only nine points of adjustment
MinorThe example spans 1973 to 2013, or four decades. At the paper's approximately three-point-per-decade rate, the adjustment would be about 12 points, yielding a mean near 112 and a cut point near 82, not 109 and 79.
“if a child were assessed in 2013 with the WISC-R standardized in 1973, we could adjust the mean to 109 (SD = 15) and the cut point for intellectual disability to 79 (3 points).”
“the Flynn effect was 2.93 points per decade”
Comparisons are counted as studies in the abstract
MinorThe methods and results identify 285 qualifying comparisons extracted from 154 empirical studies and 27 manuals, rather than 285 distinct studies.
“Across 285 studies (N = 14,031) since 1951”
“One hundred and fifty-four empirical studies and 27 test manuals met inclusion criteria, from which 378 comparisons were extracted, 285 of which were normed more than 5 years apart.”
WISC-R norming year changes from 1972 to 1973
MinorThe paper uses 1972 as the WISC-R norming year in its worked example, but calls the same test standardized in 1973 in the conclusion.
“the year in which the test was normed (1972)”
“the WISC-R standardized in 1973”
Citations
Cites
Diagnostic and Statistical Manual of Mental Disorders
Williams, J. B. W., & First, M. B. (2013) · Oxford University Press eBooks · doi:10.1093/acrefore/9780199975839.013.104 · Cited by 109,845
Borenstein, M., Hedges, L. V., Higgins, J. P. T., & Rothstein, H. R. (2021) · doi:10.1002/9781119558378 · Cited by 9,799
(2000) · Cited by 9,198
Wechsler Abbreviated Scale of Intelligence
Dumont, R., Willis, J. O., Veizel, K., & Zibulsky, J. (2014) · Wiley eBooks · doi:10.1002/9781118660584.ese2519 · Cited by 5,546
Wechsler Intelligence Scale for Children
Miles-Mason, E. (2018) · Sage eBooks · doi:10.4135/9781483392271.n537 · Cited by 4,133
Massive IQ gains in 14 nations: What IQ tests really measure.
Flynn, J. R. (1987) · Psychological Bulletin · doi:10.1037/0033-2909.101.2.171 · Cited by 1,918 · cited 7×
“An alternate approach, taken by Flynn (1987) and others since (e.g., Sundet et al., 2004, 2008), broadens the perspective from intragroup to intergroup change by focusing on draft board test performance within countries in the practice of administering IQ tests to all young men being assessed for…”
BackgroundMethodResultInfluentialInference by Eye: Confidence Intervals and How to Read Pictures of Data.
Cumming, G., & Finch, S. (2005) · American Psychologist · doi:10.1037/0003-066x.60.2.170 · Cited by 1,449
Intellectual disability : definition, classification, and systems of supports
Disabilities, D. (2010) · Medical Entomology and Zoology · Cited by 1,370
The mean IQ of Americans: Massive gains 1932 to 1978.
Flynn, J. R. (1984) · Psychological Bulletin · doi:10.1037/0033-2909.95.1.29 · Cited by 1,206
Kaufman Brief Intelligence Test
(2012) · Springer eBooks · doi:10.1007/springerreference_183806 · Cited by 1,089
Flagged first, then by citations
Research works printed but not linked: 17
- Doll B Boren R Performance of severely language-impaired students on the WISC-III, language scales, and academic achievement measures Journal of Psychoeducational Assessment, Advances in Psychological Assessment Monograph Series 1993 77 86
- Edwards BR Klein M Comparison of the WAIS and the WAIS-R with Ss of high intelligence Journal of Clinical Psychology 1984 40 1 300 302
- Elley WB Changes in mental ability in New Zealand New Zealand Journal of Educational Studies 1969 4 140 155
- Flynn JR Flores-Mendoza C Colom R Efeito Flynn: Repensando a inteligência e seus efeitos [The Flynn effect: Rethinking intelligence and what affects it] Introdução à psicologia das diferenças individuais [Introduction to the psychology of individual differences] 2006b Porto Alegre, Brasil ArtMed 387 411 (English trans. available from jim.flynn@stonebow.otago.ac.nz).
- Flynn JR What is intelligence? 2007 Cambridge Cambridge University Press
- Klanderman J Devine J Mollner C The K-ABC: A construct validity study with the WISC-R and Stanford-Binet Journal of Clinical Psychology 1985 41 2 273 281
- McGinley P A comparison of WISC and WISC-R test results The Irish Journal of Psychology 1981 1 23 24 doi:
- Phelps L Leguori S Nisewaner K Parker M Practical interpretations of the WISC-III with language-disordered children Journal of Psychoeducational Assessment WISC-III Monograph 1993 71 76
- Quereshi MY McIntire DH The comparability of the WISC, WISC-R, and WPPSI Journal of Clinical Psychology 1984 40 4 1036 1043
- Robinson EL Nagle RJ The comparability of the Test of Cognitive Skills with the Wechsler Intelligence Scale for Children-Revised and the Stanford-Binet: Fourth Edition with gifted children Psychology in the Schools 1992 29 2 107 112
- Rothlisberg BA Comparing the Stanford-Binet, Fourth Edition to the WISC-R: A concurrent validation study Journal of School Psychology 1987 25 2 193 196
- Thorndike RL Hagen EP Sattler JM Stanford-Binet Intelligence Scale, Fourth Edition, Technical manual 1986 Chicago, IL The Riverside Publishing Company
- Wechsler D Wechsler Intelligence Scale for Children, Third Edition, Manual 1991 San Antonio, TX The Psychological Corporation
- Wechsler D Wechsler Adult Intelligence Scale, Third Edition, Technical manual 1997 San Antonio, TX The Psychological Corporation
- Wechsler D Wechsler Preschool and Primary Scale of Intelligence, Third Edition, Technical manual 2002 San Antonio, TX The Psychological Corporation
- Wechsler D Wechsler Adult Intelligence Scale, Fourth Edition, Technical manual 2008 San Antonio, TX The Psychological Corporation
- Zimmerman IL Woo-Sam J The utility of the Wechsler Preschool and Primary Scale of Intelligence in the public school Journal of Clinical Psychology 1970 26 4 472
Cited by
Sorted by citations
Maintenance, reserve and compensation: the cognitive neuroscience of healthy ageing
Cabeza, R., Albert, M., Belleville, S., Craik, F. I. M., Duarte, A., Grady, C. L., Lindenberger, U., Nyberg, L., Park, D. C., Reuter-Lorenz, P. A., et al. (2018) · Nature Reviews Neuroscience · doi:10.1038/s41583-018-0068-2 · Cited by 1,298
Innovation in the collective brain
Muthukrishna, M., & Henrich, J. (2016) · Philosophical Transactions of the Royal Society B Biological Sciences · doi:10.1098/rstb.2015.0192 · Cited by 441
Cultural Change: The How and the Why
Varnum, M. E. W., & Grossmann, I. (2017) · Perspectives on Psychological Science · doi:10.1177/1745691617699971 · Cited by 294
Gender differences in individual variation in academic grades fail to fit expected patterns for STEM
O’Dea, R. E., Lagisz, M., Jennions, M. D., & Nakagawa, S. (2018) · Nature Communications · doi:10.1038/s41467-018-06292-0 · Cited by 253
Nyberg, L. H., & Pudas, S. (2018) · Annual Review of Psychology · doi:10.1146/annurev-psych-010418-103052 · Cited by 272
Invisible Hands and Fine Calipers: A Call to Use Formal Theory as a Toolkit for Theory Construction
Robinaugh, D. J., Haslbeck, J. M. B., Ryan, O., Fried, E. I., & Waldorp, L. (2021) · Perspectives on Psychological Science · doi:10.1177/1745691620974697 · Cited by 237
“Theories explain phenomena: the robust, generalizable features of the world that we as scientists seek to understand (Bogen & Woodward, 1988; Haig, 2014), such as the Flynn Effect (Trahan et al., 2014), the matching phenomenon (Feingold, 1988), or the simple observation that some individuals experience recurrent panic…”
BackgroundThe Neuroscience of Intelligence
Haier, R. J. (2016) · Cambridge University Press eBooks · doi:10.1017/9781316105771 · Cited by 209
Ronfani, L., Brumatti, L. V., Mariuz, M., Tognin, V., Bin, M., Ferluga, V., Knowles, A., Montico, M., & Barbone, F. (2015) · PLoS ONE · doi:10.1371/journal.pone.0127052 · Cited by 182
“It must be emphasized, however, that the high IQ score could be explained by the Flynn effect, which refers to the observed rise in IQ scores over time resulting in norms becoming obsolete [43], as indeed is the case for the Italian norms of the Raven test.”
BackgroundSauce, B., & Matzel, L. D. (2017) · Psychological Bulletin · doi:10.1037/bul0000131 · Cited by 185
“Worldwide, a meta-analysis of 53 studies conducted in industrialized societies showed an increase of 17.6 IQ points occurred between 1951–2011, translating to an average increase of approximately 2.9 IQ points per decade (Trahan et al., 2014).”
InfluentialAssociation of Very Preterm Birth or Very Low Birth Weight With Intelligence in Adulthood
Eves, R., Mendonça, M., Baumann, N., Ni, Y., Darlow, B. A., Horwood, L. J., Woodward, L. J., Doyle, L. W., Cheong, J. L. Y., Anderson, P. J., et al. (2021) · Archives of Pediatrics and Adolescent Medicine · doi:10.1001/jamapediatrics.2021.1058 · Cited by 170
Selection against variants in the genome associated with educational attainment
Kong, A., Frigge, M. L., Thorleifsson, G., Stefansson, H., Young, A. I., Zink, F., Jonsdottir, G. A., Okbay, A., Sulem, P., Masson, G., et al. (2017) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.1612113114 · Cited by 168
Personality and intelligence: A meta-analysis.
Anglim, J., Dunlop, P. D., Wee, S., Horwood, S., Wood, J. K., & Marty, A. (2022) · Psychological Bulletin · doi:10.1037/bul0000373 · Cited by 125
The Wisdom Researchers and the Elephant: An Integrative Model of Wise Behavior
Glück, J., & Weststrate, N. M. (2022) · Personality and Social Psychology Review · doi:10.1177/10888683221094650 · Cited by 125
“Societies are more intelligent (Trahan et al., 2014) and educated (Hashiguchi et al., 2015) than ever before, but, despite many promising advancements in the medical and technological industries, we confront an unprecedented array of social and environmental problems, many of which are human-made.”
BackgroundMisconceptions of Measurement Equivalence
Welzel, C., & Inglehart, R. (2016) · Comparative Political Studies · doi:10.1177/0010414016628275 · Cited by 102
Gerstorf, D., Hülür, G., Drewelies, J., Eibich, P., Düzel, S., Demuth, I., Ghisletta, P., Steinhagen‐Thiessen, E., Wagner, G. G., & Lindenberger, U. (2015) · Psychology and Aging · doi:10.1037/pag0000016 · Cited by 105
Cultural evolution of genetic heritability
Uchiyama, R., Spicer, R., & Muthukrishna, M. (2021) · Behavioral and Brain Sciences · doi:10.1017/s0140525x21000893 · Cited by 103
Teachers need more than knowledge: Why motivation, emotion, and self-regulation are indispensable
Pekrun, R. H. (2021) · Educational Psychologist · doi:10.1080/00461520.2021.1991356 · Cited by 104
“A prime example is the increase of average levels of intelligence during the 20th century (“Flynn effect”; Bratsberg & Rogeberg, 2018; Trahan et al., 2014), which occurred despite substantial heritability.”
BackgroundNygaard, E., Slinning, K., Moe, V., & Walhovd, K. (2017) · Child Neuropsychology: A Journal of Normal and Abnormal Development in Childhood and Adolescence · doi:10.1080/09297049.2015.1092509 · Cited by 84
Drewelies, J., Huxhold, O., & Gerstorf, D. (2019) · Psychology and Aging · doi:10.1037/pag0000423 · Cited by 90
Kobayashi, L. C., Glymour, M. M., Kahn, K., Payne, C., Wagner, R. G., Montana, L. S., Mateen, F. J., Tollman, S. M., & Berkman, L. F. (2017) · Social Science & Medicine · doi:10.1016/j.socscimed.2017.08.009 · Cited by 79
Lindert, P. H. (2021) · Cambridge University Press eBooks · doi:10.1017/9781108784467 · Cited by 79
Cognitive capitalism human capital and the wellbeing of nations
Rindermann, H. (2018) · Cited by 77
Comparison of cognitive and physical functioning of Europeans in 2004-05 and 2013
Ahrenfeldt, L. J., Lindahl‐Jacobsen, R., Rizzi, S., Thinggaard, M., Christensen, K., & Vaupel, J. W. (2018) · International Journal of Epidemiology · doi:10.1093/ije/dyy094 · Cited by 77
“In the population as a whole, cognition is generally improving in later-born cohorts (the Flynn effect).(8,9) These positive trends seem to persist into late adulthood, but perhaps not into the final years of life.”
BackgroundRijnen, S. J. M., Meskal, I., Emons, W. H. M., Campman, C. A. M., van der Linden, S. D., Gehring, K., & Sitskoorn, M. M. (2017) · Assessment · doi:10.1177/1073191117727346 · Cited by 71
“Explanations for the Flynn effect include genetic, environmental, methodological, and measurement factors (Flynn, 1984; Trahan, Stuebing, Hiscock, & Fletcher, 2014).”
BackgroundYi, Y. G., Sung, I. Y., & Yuk, J. S. (2018) · Annals of Rehabilitation Medicine · doi:10.5535/arm.2018.42.2.313 · Cited by 67
“According to recent studies on the Flynn effect, the score generally has a tendency to decrease, and children have a smaller score change than adults [12].”
BackgroundResultAssessments of neurocognitive and behavioral function in the mucopolysaccharidoses
Shapiro, E., Escolar, M. L., Delaney, K. A., & Mitchell, J. J. (2017) · Molecular Genetics and Metabolism · doi:10.1016/j.ymgme.2017.09.007 · Cited by 62
Havinga, P., Boschloo, L., Bloemen, A. J. P., Nauta, M. H., de Vries, S. O., Penninx, B. W. J. H., Schoevers, R. A., & Hartman, C. A. (2016) · The Journal of Clinical Psychiatry · doi:10.4088/jcp.15m09936 · Cited by 69
Drewelies, J., Deeg, D. J. H., Huisman, M. A., & Gerstorf, D. (2018) · Psychology and Aging · doi:10.1037/pag0000276 · Cited by 62
Is There Really a Creativity Crisis? A Critical Review and Meta‐analytic Re‐Appraisal
Barbot, B., & Said‐Metwaly, S. (2020) · The Journal of Creative Behavior · doi:10.1002/jocb.483 · Cited by 64
Assessment of Specific Learning Disabilities and Intellectual Disabilities
Fletcher, J. M., & Miciak, J. (2023) · Assessment · doi:10.1177/10731911231194992 · Cited by 79
“The rate is conventionally estimated at 0.3 points per year, or 3 points per decade, which is supported by two major meta-analyses (Pietschnig & Voracek, 2015; Trahan et al., 2014).”
BackgroundInfluentialSelf-citationA negative Flynn effect in France, 1999 to 2008–9
Dutton, E., & Lynn, R. (2015) · Intelligence · doi:10.1016/j.intell.2015.05.005 · Cited by 58
Clinical practice guidelines for assessment and management of intellectual disability
Seshadri, S. P., Kishore, M. T., & Udipi, G. (2019) · Indian Journal of Psychiatry · doi:10.4103/psychiatry.indianjpsychiatry_507_18 · Cited by 57
Leonhard, M. J., Chang, E. T., Loccisano, A. E., & Garry, M. R. (2019) · Toxicology · doi:10.1016/j.tox.2019.03.004 · Cited by 52
Grossmann, K. R., Westblad, M. E., Blennow, M., & Lindström, K. (2022) · Archives of Disease in Childhood Fetal & Neonatal · doi:10.1136/archdischild-2022-324418 · Cited by 52
Gerstorf, D., Drewelies, J., Düzel, S., Smith, J., Wahl, H.-W., Schilling, O. K., Kunzmann, U., Siebert, J., Katzorreck, M., Eibich, P., et al. (2019) · Psychology and Aging · doi:10.1037/pag0000389 · Cited by 53
个人主义上升, 集体主义式微?——全球文化变迁与民众心理变化
HUANG, Z., Jing, Y., Yu, F., Gu, R., Zhou, X., Zhang, J., & Cai, H. (2018) · Advances in Psychological Science · doi:10.3724/sp.j.1042.2018.02068 · Cited by 47
Osler, M., Christensen, G. T., Garde, E., Mortensen, E. L., & Christensen, K. (2017) · Alzheimer s & Dementia · doi:10.1016/j.jalz.2017.04.003 · Cited by 43
Wongupparaj, P., Wongupparaj, R., Kumari, V., & Morris, R. G. (2017) · Intelligence · doi:10.1016/j.intell.2017.07.006 · Cited by 45
People tend to overestimate their romantic partner's intelligence even more than their own
Gignac, G. E., & Zajenkowski, M. (2019) · Intelligence · doi:10.1016/j.intell.2019.01.004 · Cited by 59
Wald, E. L. A. F., Hendriksen, J. G. M., Drenthen, G. S., van Kuijk, S. M. J., Aldenkamp, A. P., Vles, J. S. H., Vermeulen, R. J., Hall, M. H. J. A. D.-V., & Klinkenberg, S. (2019) · Neuropsychology Review · doi:10.1007/s11065-019-09419-2 · Cited by 42
Measuring early child development across low and middle-income countries: A systematic review
Chereau, B. M., Ang, L., Dockrell, J. E., Outhwaite, L. A., & Heffernan, C. (2021) · Journal of Early Childhood Research · doi:10.1177/1476718x211020031 · Cited by 41
“Norms must also be current as they become outdated by about three points a decade (Trahan et al., 2014).”
BackgroundNyberg, J., Henriksson, M., Wall, A., Vestberg, T., Westerlund, M., Walser, M., Eggertsen, R., Danielsson, L., Kuhn, H. G., Åberg, N. D., et al. (2021) · BMC Psychiatry · doi:10.1186/s12888-021-03618-z · Cited by 46
IQ AND SOCIOECONOMIC DEVELOPMENT ACROSS REGIONS OF THE UK
Carl, N. (2015) · Journal of Biosocial Science · doi:10.1017/s002193201500019x · Cited by 41
The positive plasticity of adult development: Potential for the 21st century.
Staudinger, U. M. (2020) · American Psychologist · doi:10.1037/amp0000612 · Cited by 47
Improving the detection of detainees with suspected intellectual disability in police custody
McKinnon, I., Thorp, J., & Грубин, Д. (2015) · Advances in Mental Health and Intellectual Disabilities · doi:10.1108/amhid-04-2015-0015 · Cited by 39
Kuo, S. S., & Eack, S. M. (2020) · Frontiers in Psychiatry · doi:10.3389/fpsyt.2020.00187 · Cited by 37
A Review of Screeners to Identify Risk of Developmental Language Disorder
Bao, X., Komesidou, R., & Hogan, T. P. (2024) · American Journal of Speech-Language Pathology · doi:10.1044/2023_ajslp-23-00286 · Cited by 35
Dworak, E. M., Revelle, W., & Condon, D. M. (2023) · Intelligence · doi:10.1016/j.intell.2023.101734 · Cited by 35
Hofer, G., Mraulak, V., Grinschgl, S., & Neubauer, A. C. (2022) · Journal of Intelligence · doi:10.3390/jintelligence10010010 · Cited by 40
Cutting, J. E. (2021) · doi:10.1093/oso/9780197567777.001.0001 · Cited by 52
Long-term neurocognitive outcomes in 204 single-suture craniosynostosis patients
Junn, A. H., Long, A. S., Hauc, S. C., Almeida, M. N., Alper, D. P., Rivera, J. C., Mayes, L. C., Persing, J. A., & Alperovich, M. A. (2023) · Child s Nervous System · doi:10.1007/s00381-023-05908-1 · Cited by 32
“Third, upward drift of population average IQs over time when measured with the same IQ test, termed the Flynn effect, may further complicate comparisons of IQ scores between studies [54].”
Smarter every day: The deceleration of population ageing in terms of cognition
Bordone, V., Scherbov, S., & Steiber, N. (2015) · Intelligence · doi:10.1016/j.intell.2015.07.005 · Cited by 35
Pollution, Ability, and Gender-Specific Investment Responses to Shocks
Molina, T. (2020) · Journal of the European Economic Association · doi:10.1093/jeea/jvaa005 · Cited by 32
Platt, J. M., Keyes, K. M., McLaughlin, K. A., & Kaufman, A. S. (2019) · Intelligence · doi:10.1016/j.intell.2019.101385 · Cited by 32
“However, previous studies differ in quality (Trahan et al., 2014) and often rely on small sample sizes at the lower end of the IQ distribution (Zhou et al.”
BackgroundMethodResultInfluentialMenie, M. A. W. O., Fernandes, H. B. F., Figueredo, A. J., & Meisenberg, G. (2015) · Frontiers in Psychology · doi:10.3389/fpsyg.2015.00361 · Cited by 31
Norms for standard neuropsychological tests from the French CONSTANCES cohort
Ouvrard, C., Berr, C., Meillon, C., Ribet, C., Goldberg, M., Zins, M., & Amieva, H. (2018) · European Journal of Neurology · doi:10.1111/ene.13890 · Cited by 30
“Indeed, cognitive abilities improve from one generation to the next [11].”
BackgroundUnderstanding Replication in a Way That Is True to Science
Haig, B. D. (2021) · Review of General Psychology · doi:10.1177/10892680211046514 · Cited by 36
“More than this, the robustness of the Flynn effect was affirmed by a subsequent meta-analysis (Trahan et al., 2014), which confirmed earlier estimates of the Flynn effect and its stability across different countries, age groups, samples, measures, and levels of performance.”
ResultHessel, P., Kinge, J. M., Skirbekk, V., & Staudinger, U. M. (2018) · Journal of Epidemiology & Community Health · doi:10.1136/jech-2017-209979 · Cited by 34
Drewelies, J., Agrigoroaei, S., Lachman, M. E., & Gerstorf, D. (2018) · Developmental Psychology · doi:10.1037/dev0000527 · Cited by 34
Intellectual development of childhood ALL patients: a multicenter longitudinal study
Sleurs, C., Lemiere, J., Vercruysse, T., Nolf, N., CALSTER, B. V., Deprez, S., Renard, M., Vandecruys, E., Benoît, Y., & Uyttebroeck, A. (2016) · Psycho-Oncology · doi:10.1002/pon.4186 · Cited by 30
“, the observed rise in norm IQ scores over time, with an estimated increase of 3 IQ points per decade [39]).”
BackgroundWhat causes the anti-Flynn effect? A data synthesis and analysis of predictors
Woodley of Menie, M. A., Peñaherrera-Aguirre, M., Fernandes, H. B. F., & Figueredo, A.-J. (2018) · Evolutionary Behavioral Sciences · doi:10.1037/ebs0000106 · Cited by 29
The Flynn effect in Europe – Effects of sex and region
Weber, D., Dekhtyar, S., & Herlitz, A. (2017) · Intelligence · doi:10.1016/j.intell.2016.11.003 · Cited by 33
Lynn, R., Fuerst, J. G. R., & Kirkegaard, E. O. W. (2018) · Intelligence · doi:10.1016/j.intell.2018.04.004 · Cited by 27
Cohort Differences in Cognitive Aging in the Longitudinal Aging Study Amsterdam
Brăilean, A., Huisman, M. A., Prince, M. J., Prina, M. A., Deeg, D. J. H., & Comijs, H. C. (2016) · The Journals of Gerontology Series B · doi:10.1093/geronb/gbw129 · Cited by 33
Gerstorf, D., Ram, N., Drewelies, J., Duezel, S., Eibich, P., Steinhagen-Thiessen, E., Liebig, S., Goebel, J., Demuth, I., Villringer, A., et al. (2023) · Psychological Science · doi:10.1177/09567976221118541 · Cited by 26
Trends in Intracranial and Cerebral Volumes of Framingham Heart Study Participants Born 1930 to 1970
DeCarli, C. S., Maillard, P., Pase, M. P., Beiser, A., Kojis, D. J., Satizábal, C. L., Himali, J. J., Aparicio, H. J., Fletcher, E. M., & Seshadri, S. S. (2024) · JAMA Neurology · doi:10.1001/jamaneurol.2024.0469 · Cited by 26
Financial scarcity and cognitive performance: A meta-analysis
de Almeida, F., Scott, I. J., Soro, J. C., Fernandes, D. V. D. H., Amaral, A. R., Catarino, M. M. R. S., Arêde, A., & Ferreira, M. B. (2024) · Journal of Economic Psychology · doi:10.1016/j.joep.2024.102702 · Cited by 38
“Trahan et al. (2014) performed a meta -analysis of the Flynn effect.”
MethodShakeel, M. D., & Peterson, P. E. (2022) · Educational Psychology Review · doi:10.1007/s10648-021-09657-y · Cited by 29
“…effects” literature (Herrnstein & Murray, 1994, p.307).2 Recent meta-analyses of Flynn effects find greater growth in fluid reasoning (ability to analyze abstract relationships) than in crystallized knowledge (understanding the empirical world) (Pietschnig & Voracek, 2015; Trahan et al., 2014).”
BackgroundLabor Market Returns and the Evolution of Cognitive Skills: Theory and Evidence
Hermo, S., Päällysaho, M., Seim, D., & Shapiro, J. M. (2022) · The Quarterly Journal of Economics · doi:10.1093/qje/qjac022 · Cited by 30
The Effect of Income and Wealth on Behavioral Strategies, Personality Traits, and Preferences
Boon-Falleur, M., Baumard, N., & André, J. (2024) · Perspectives on Psychological Science · doi:10.1177/17456916231201512 · Cited by 26
“This has already been observed for a number of physiological characteristics, such as height, life expectancy, and IQ (Baten & Blum, 2014; Roser et al., 2013; Trahan et al., 2014).”
McKenzie, K., Sharples, P., & Murray, A. L. (2015) · Intellectual and developmental disabilities · doi:10.1352/1934-9556-53.4.301 · Cited by 27
“For example, although the exact magnitude of the Flynn effect can vary according to the test used and age of the participant (Beaujean & Sheng, 2014), it has been found to have an effect at all levels of ability (Trahan et al., 2014).”
BackgroundO'Reilly, D., Crushell, E., Hughes, J., Ryan, S., Rogers, Y., Borovickova, I., Mayne, P., Riordan, M., Awan, A., Carson, K., et al. (2021) · Journal of Inherited Metabolic Disease · doi:10.1002/jimd.12337 · Cited by 24
“The “Flynn Effect,” a well-described tendency for IQ scores to increase over time/generations, at a rate of approximately three IQ points per decade, may also be a contributory factor.(41) Other cohorts have also reported on neurodevelopmental outcomes however they were conducted over a shorter time frame.”
Grade Inflation or Grade Increase
Yeritsyan, A., Mjelde, J. W., & Litzenberg, K. K. (2022) · Journal of Agricultural and Applied Economics · doi:10.1017/aae.2022.15 · Cited by 26
Parental and family determinants of the Flynn effect
Rajaleid, K., & Vågerö, D. (2023) · Longitudinal and Life Course Studies · doi:10.1332/175795921x16708793393107 · Cited by 22
Ilardi, C. R., Garofalo, E., Chieffi, S., Gamboz, N., Marra, M. L., & Iavarone, A. (2020) · Neurological Sciences · doi:10.1007/s10072-020-04498-z · Cited by 22
Billeiter, K. B., & Froiland, J. M. (2022) · Child Psychiatry & Human Development · doi:10.1007/s10578-021-01300-9 · Cited by 29
“Also, physicians and psychologists serving those with ASD depend on IQ scores for determining eligibility for community, state, and federal resources; social services; special education programs; and legal consequences, such as deciding on the death penalty [18, 19].”
BackgroundThe Flynn Effect: A Quantitative Commentary on Modernity and Human Intelligence
Clark, C. M., Lawlor‐Savage, L., & Goghari, V. M. (2016) · Measurement Interdisciplinary Research and Perspectives · doi:10.1080/15366367.2016.1156910 · Cited by 25
Squires, J. E., Ng, V. L., Hawthorne, K. M., Henn, L. L., Sorensen, L. G., Fredericks, E. M., Alonso, E. M., Murray, K. F., Loomes, K. M., Karpen, S. J., et al. (2019) · Journal of Pediatric Gastroenterology and Nutrition · doi:10.1097/mpg.0000000000002489 · Cited by 21
“Described as the “Flynn Effect”, IQ scores have been observed to rise over time (40), meaning the IQ scores reported here are likely somewhat inflated.”
BackgroundBancks, M. P., Alonso, Á., Allen, N. B., Yaffe, K. S., & Carnethon, M. R. (2019) · Journal of Epidemiology & Community Health · doi:10.1136/jech-2018-211985 · Cited by 22
Kirton, J. W., Soble, J. R., Marceaux, J. C., Messerly, J. M., Bain, K. M., Webber, T. A., Fullen, C. T., Alverson, W. A., & McCoy, K. J. M. (2019) · Neuropsychology · doi:10.1037/neu0000569 · Cited by 21
Evolutionary Trajectories of Complex Traits in European Populations of Modern Humans
Kuijpers, Y., Domínguez‐Andrés, J., Bakker, O. B., Gupta, M. K., Graßhoff, M., Xu, C., Joosten, L. A. B., Bertranpetit, J., Netea, M. G., & Li, Y. (2022) · Frontiers in Genetics · doi:10.3389/fgene.2022.833190 · Cited by 23
Seventy years, 1000 samples, and 300,000 SPM scores: A new meta-analysis of Flynn effect patterns
Wongupparaj, P., Wongupparaj, R., Morris, R. G., & Kumari, V. (2023) · Intelligence · doi:10.1016/j.intell.2023.101750 · Cited by 24
Kids These Days! Increasing delay of gratification ability over the past 50 years in children
Protzko, J. (2020) · Intelligence · doi:10.1016/j.intell.2020.101451 · Cited by 25
Gonthier, C., Grégoire, J., & Besançon, M. (2021) · Intelligence · doi:10.1016/j.intell.2020.101512 · Cited by 20
Cohort and Period Effects as Explanations for Declining Dementia Trends and Cognitive Aging
Clouston, S., Terrera, G. M., Rodgers, J. L., O’Keefe, P., Mann, F. D., Lewis, N. A., Wänström, L., Kaye, J. A., & Hofer, S. M. (2021) · Population and Development Review · doi:10.1111/padr.12409 · Cited by 21
Olaithe, M., Weinborn, M., Lowndes, T. A., Ng, A., Hodgson, E., Fine, L., Parker, D. J., Pushpanathan, M. E., Bayliss, D. M., Anderson, M. B., et al. (2018) · Archives of Clinical Neuropsychology · doi:10.1093/arclin/acy102 · Cited by 19
Marrie, R. A., Whitehouse, C. E., Patel, R., Figley, C. R., Kornelsen, J., Bolton, J. M., Graff, L. A., Mazerolle, E. L., Marriott, J. J., Bernstein, C. N., et al. (2021) · Frontiers in Neurology · doi:10.3389/fneur.2020.621010 · Cited by 20
Gonthier, C., & Grégoire, J. C. (2022) · Intelligence · doi:10.1016/j.intell.2022.101688 · Cited by 22
Visual‐Motor Integration Skills
Santi, K. L., Francis, D. J., Currie, D. C., & Wang, Q. (2014) · Optometry and Vision Science · doi:10.1097/opx.0000000000000473 · Cited by 19
“The slightly elevated performance on the WISC subtests reflects norms obsolescence known as the Flynn Effect, which accounts for a growth in mean IQ of about 3 points per decade, as indicated in a recent meta-analysis by Trahan et al.(34,35)”
MethodA Revision Process That Bridges Qualitative and Quantitative Assessment
Stroud, L. A., Green, E., & Cronje, J. H. (2020) · Psychology · doi:10.4236/psych.2020.113029 · Cited by 33
“A meta-analysis conducted on 285 studies confirmed previous estimates of the Flynn effect across various ages (Trahan et al., 2014).”
MethodDoes in utero exposure of antiepileptic drugs lead to failure to reach full cognitive potential?
McCorry, D., & Bromley, R. (2015) · Seizure · doi:10.1016/j.seizure.2015.01.019 · Cited by 16
Ris, M. D., Grosch, M. C., Fletcher, J. M., Metah, P., & Kahalley, L. S. (2016) · The Clinical Neuropsychologist · doi:10.1080/13854046.2016.1216070 · Cited by 17
Self-citationChild development assessment: Practitioner input in the revision for Griffiths III
Green, E. M., Stroud, L. A., Marx, C., & Cronje, J. H. (2020) · Child Care Health and Development · doi:10.1111/cch.12796 · Cited by 18
Cross‐sectional and longitudinal assessment of cognitive development in Williams syndrome
Farran, E. K., Purser, H. R. M., Jarrold, C., Thomas, M. S. C., Scerif, G., Stojanovik, V., & Herwegen, J. V. (2023) · Developmental Science · doi:10.1111/desc.13421 · Cited by 16
“Due to assessments being used over a wide timespan (date-of-test for our sample ranges from 1997 to 2018 for PC, 1998 to 2015 for RCPM and 2009 to 2016 for BPVS), the presence of a Flynn effect (population gains on standardised intelligence tests; Trahan et al., 2014) was assessed.”
MethodIntegrating Intra- and Interindividual Phenomena in Psychological Theories
Borsboom, D., & Haslbeck, J. M. B. (2024) · Multivariate Behavioral Research · doi:10.1080/00273171.2024.2336178 · Cited by 23
“For instance, robust differences between cohorts, such as the secular gains in IQ known as the Flynn effect (Trahan et al., 2014), constitute a robust phenomenon in the study of intelligence, and cross-cultural differences may similary consitute robust phenomena in and of themselves (Henrich et…”
Future Cognitive Ability: US IQ Prediction until 2060 Based on NAEP
Rindermann, H., & Pichelmann, S. (2015) · PLoS ONE · doi:10.1371/journal.pone.0138412 · Cited by 18
Fluid Ability (Gf) and Complex Problem Solving (CPS)
Kyllonen, P. C., Anguiano‐Carrasco, C., & Kell, H. J. (2017) · Journal of Intelligence · doi:10.3390/jintelligence5030028 · Cited by 20
Prien, A., Junge, A., Brugger, P., Straumann, D., & Feddermann‐Demont, N. (2018) · Archives of Clinical Neuropsychology · doi:10.1093/arclin/acy056 · Cited by 16
Neurodevelopmental Outcomes in Children With Inherited Liver Disease and Native Liver
Leung, D. H., Sorensen, L. G., Ye, W., Hawthorne, K. M., Ng, V. L., Loomes, K. M., Fredericks, E. M., Alonso, E. M., Heubi, J. E., Horslen, S. P., et al. (2021) · Journal of Pediatric Gastroenterology and Nutrition · doi:10.1097/mpg.0000000000003337 · Cited by 16
Giangrande, E. J., Beam, C. R., Finkel, D., Davis, D. W., & Turkheimer, E. N. (2021) · Child Development · doi:10.1111/cdev.13675 · Cited by 15
“Findings regarding the relative strength of the FE at different stages of development have been inconsistent, with one metaanalysis observing larger effects in adults than in children (Pietschnig & Voracek, 2015) and another finding no differences across ages (Trahan et al., 2014).”
Result
Metadata
- Authors
- Trahan, L. H., Stuebing, K. K., Fletcher, J. M., & Hiscock, M.
- Affiliations
- University of Houston (US)
- Venue
- Psychological Bulletin
- Published
- 2014
- Volume
- 140
- Issue
- 5
- Pages
- 1332-1360
- ISSN
- 0033-2909 (ISSN-L)
- 1939-1455
- PMC
- PMC4152423
- OpenAlex
- W2164636756
- Cited by
- 364
- References
- 262
- Citations by year
- 2026: 24 · 2025: 38 · 2024: 33 · 2023: 30 · 2022: 36 · 2021: 56 · 2020: 34 · 2019: 20 · 2018: 32 · 2017: 16 · 2016: 20 · 2015: 22 · 2014: 2
- FWCI
- 27.60
- Type
- journal article
- Language
- en
- Open access
- green
- www.ncbi.nlm.nih.gov
- Locations
- Psychological Bulletin (publishedVersion)
- PubMed (publishedVersion)
- PubMed Central (acceptedVersion)
- Funders
- Novartis Foundation
- University of Cambridge
- Eunice Kennedy Shriver National Institute of Child Health and Human Development (P50HD052117)
- Topics
- Social Sciences › Psychology › Experimental and Cognitive Psychology › Cognitive Abilities and Testing
- Social Sciences › Decision Sciences › Management Science and Operations Research › Psychometric Methodologies and Testing
- Social Sciences › Sociology and Political Science › Intergenerational and Educational Inequality Studies
- Keywords
- Flynn effect, IQ trends, Stanford-Binet, measurement error, effect size, validation samples
- MeSH terms
- Capital Punishment, Education, Special, Humans, Intelligence, Intelligence Tests, Intellectual Disability
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
A language model drew the claims from the paper on 2026-11-03, under version 3 of the claim definition (model deepseek-v4.1-flash, prompt extract-v3).
A second model labelled each claim on 2026-11-03 (model jev-1.13-20260917, definition revision gold-guideline-v0.2).
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
Are you an author, or do you see a problem with this page? Request a review
