Kanazawa [Kanazawa, S. (2006). IQ and the wealth of states. Intelligence, 34, 593–600.] offered estimates of state IQ derived from SAT data. The purpose of this commentary is to argue that state preferences for the use of the ACT versus the SAT create biased estimates of SAT-derived state IQ for states where the ACT is more frequently used than the SAT. This error can be reduced by using both A...

IQ and Family Background: Are Associations Strong or Weak? For the purpose of understanding the underlying mechanisms behind intergenerational associations in income and education, recent studies have explored the intergenerational transmission of abilities. We use a large representative sample of Swedish men to examine both intergenerational and sibling correlations in IQ. Since siblings share...

BACKGROUND The intelligence of individuals with Autism Spectrum Disorder (ASD) varies considerably. The pattern of cognitive deficits associated with ASD may differ depending on intelligence. We aimed to study the absolute and relative severity of cognitive deficits in participants with ASD in relation to IQ. METHODS A total of 274 children (M age = 12.1, 68.6% boys) participated: 30 ASD and ...

Sumnzary.-Within each of 18 classrooms, an average of 20% of the children were reported to classroom teachers as showing unusual potential for intellectual gains. Eight nonths later these "unusual" children (who had actually been selected at random) showed significantly greater gains in IQ than did the remaining children in th: control group. These effects of teachers' expectancies operated pri...

OBJECTIVES/HYPOTHESIS In this meta-analysis, we reviewed observational studies investigating differences in intelligence quotient (IQ) scores of children with unilateral hearing loss compared to children with normal hearing. DATA SOURCES PubMed Medline, Cumulative Index to Nursing and Allied Health Literature, Embase, PsycINFO. METHODS A query identified all English-language studies related...

Some researchers have compared neuropsychological performance in schizophrenia groups with and without presumed IQ decline. Inherent in this approach is an assumption that group differences are due to different IQ trajectories (stable vs. declining), but neuropsychological differences could be a function of current IQ regardless of the presence or absence of previous IQ decline. We examined thi...

Morphometric neuroimaging studies on healthy adult individuals regularly report a positive association between intelligence test performance (IQ) and structural properties of the corpus callosum (CC). At the same time, studies examining the effect of callosotomy on epilepsy patients report only negligible changes in IQ as result of the surgery, partially contradicting the findings of the morpho...

Parental ages are increasing in the developed world, and postponed parenthood may have a negative association with the cognitive ability of offspring. There is, however, inconclusive evidence regarding the impact of both maternal and paternal ages. We have been able to reduce or eliminate unobserved confounding by using methods that account for fixed parental characteristics shared by brothers....

PURPOSE To evaluate intelligence quotient (IQ) in patients with congenital strabismus. METHODS All patients with congenital strabismus scheduled for surgery were enrolled consecutively over a one year period in a cross-sectional study and were evaluated for verbal, performance and total IQ scores, and compared to the mean normal IQ of 100±15. RESULTS During the study period, 109 patients wi...