Universal Nonverbal Intelligence Test Research Articles

Effects of Discontinue Rules on Psychometric Properties of Test Scores.

This paper provides results on a form of adaptive testing that is used frequently in intelligence testing. In these tests, items are presented in order of increasing difficulty. The presentation of items is adaptive in the sense that a session is discontinued once a test taker produces a certain number of incorrect responses in sequence, with subsequent (not observed) responses commonly scored as wrong. The Stanford-Binet Intelligence Scales (SB5; Riverside Publishing Company, 2003) and the Kaufman Assessment Battery for Children (KABC-II; Kaufman and Kaufman, 2004), the Kaufman Adolescent and Adult Intelligence Test (Kaufman and Kaufman 2014) and the Universal Nonverbal Intelligence Test (2nd ed.) (Bracken and McCallum 2015) are some of the many examples using this rule. He and Wolfe (Educ Psychol Meas 72(5):808-826, 2012. https://doi.org/10.1177/0013164412441937 ) compared different ability estimation methods in a simulation study for this discontinue rule adaptation of test length. However, there has been no study, to our knowledge, of the underlying distributional properties based on analytic arguments drawing on probability theory, of what these authors call stochastic censoring of responses. The study results obtained by He and Wolfe (Educ Psychol Meas 72(5):808-826, 2012. https://doi.org/10.1177/0013164412441937 ) agree with results presented by DeAyala et al. (J Educ Meas 38:213-234, 2001) as well as Rose et al. (Modeling non-ignorable missing data with item response theory (IRT; ETS RR-10-11), Educational Testing Service, Princeton, 2010) and Rose et al. (Psychometrika 82:795-819, 2017. https://doi.org/10.1007/s11336-016-9544-7 ) in that ability estimates are biased most when scoring the not observed responses as wrong. This scoring is used operationally, so more research is needed in order to improve practice in this field. The paper extends existing research on adaptivity by discontinue rules in intelligence tests in multiple ways: First, an analytical study of the distributional properties of discontinue rule scored items is presented. Second, a simulation is presented that includes additional scoring rules and uses ability estimators that may be suitable to reduce bias for discontinue rule scored intelligence tests.

Exploratory and Confirmatory Factor Analysis of the Universal Nonverbal Intelligence Test-Second Edition: Testing Dimensionality and Invariance Across Age, Gender, Race, and Ethnicity.

This study examined key assumptions underlying the interpretation of one of the most widely used multidimensional nonverbal tests of intelligence, the Universal Nonverbal Intelligence Test-Second Edition (UNIT2). Specifically, we examined the dimensionality of the UNIT2 and the interpretive relevance of its factors. We also examined the invariance of constructs measured by the UNIT2 across age groups, gender, race, and ethnicity. Structural analyses were conducted using data from 1,802 individuals aged 5 to 21 years who participated in the norming of the UNIT2. Results indicate that the UNIT2 is primarily a measure of psychometric g. Tests of invariance indicate that the factors measured by the UNIT2 are calibrated differently across age, gender, and racial groups. The Memory, Quantitative, and Reasoning factors represent psychometric g quite well. However, there is insufficient unique, reliable variance for the interpretation of the index scores reflecting the Memory, Quantitative, and Reasoning factors. Based on the results of this study, we question whether the administration of multidimensional nonverbal tests of intelligence is worth the time and effort when unidimensional tests may provide the same information.

General intelligence is associated with subclinical inflammation in Nepalese children: A population-based plasma proteomics study

Improving child cognition in impoverished countries is a public health priority. Yet, biological pathways and associated biomarkers of impaired cognition remain poorly understood and largely unknown, respectively. This study aimed to explore and quantify associations between functional plasma protein biomarkers and childhood intellectual test performance. We applied proteomics to quantify proteins in plasma samples of 249 rural Nepalese children, 6–8years of age who, 1year later at 7–9years of age, were administered the Universal Nonverbal Intelligence Test (UNIT). Among 751 plasma proteins quantified, 22 were associated with UNIT scores, passing a false discovery rate threshold of 5.0% (q<0.05). UNIT scores were higher by 2.3–9.2 points for every 50% increase in relative abundance of two insulin-like growth factor binding proteins (IGFBPs), six subclasses of apolipoprotein (Apo) and transthyretin, and lower by 4.0–15.3 points for each 50% increase in relative abundance of 13 proteins predominantly involved in inflammation. Among them, IGFBP-acid labile subunit, orosomucoid 1 (ORM1), Apo C-I, and pyruvate kinase isoenzymes M1/M2 jointly explained 37% of the variance in UNIT scores. After additional adjustment for height-for-age Z-score and household socio-economic status as indicators of long-term nutritional and social stress, associations with 6 proteins involved in inflammation, including ORM1, α-1-antichymotrypsin, reticulocalbin 1, and 3 components of the complement cascade, remained significant (q<0.05). Using untargeted proteomics, stable, constitutive facets of subclinical inflammation were associated with lower developmental test performance in this rural South Asian child population. Plasma proteomics may offer opportunities to identify functional, antecedent biomarkers of child cognitive development.

Determinants of Body Mass Index and Intelligence Quotient of Elementary School Children in Mountain Area of Nepal: An Explorative Study.

The physical growth and cognitive development of elementary school children are very crucial and this group is large in number but has little research dedicated to it. The physical growth and cognitive development of children occur simultaneously and can be measured by body mass index (BMI) and intelligence quotient (IQ). Previous studies could not sufficiently focus on both aspects. The aim of this study was to identify determinants of BMI and IQ of students in two elementary schools in the Humla district of Nepal. Two randomly selected elementary schools and all children available there (n = 173) participated in the study. BMI was calculated with the objective of proper measurement of height and weight of the children. Likewise, the updated universal nonverbal intelligence test (UNIT) was applied for IQ. Descriptive statistics, t-test, analysis of variance and multiple linear regressions were used when appropriate. Study findings showed that one-tenth of the children had grade 2 thinness (-2SD) and about one-third had poor IQ (<85). The age of the children (p < 0.05) and household economic status (p < 0.001) were significant for the BMI. Likewise, frequencies of illness in the previous year, mother’s education (p < 0.05) and father’s education (p < 0.001) were significant factors for the IQ score. More commonly, BMI and IQ scores were significantly lower in the ultra-poor group. Economic status and parent education are still major determinants of IQ and BMI in these students. Special programs and strategies should be launched to improve the poor ranking of IQ and BMI.

The Role of Pre-Primary Classes on School-Age Cognition in Rural Nepal

In rural Nepal, we assessed the factors associated with pre-primary school attendance and its relationship to cognitive testing and school progress. Sociodemographic, household, and schooling data were collected among 1466 children age 7-9 years from Sarlahi, Nepal. We performed the Universal Nonverbal Intelligence Test, backward digit span, go/no-go test, Movement Assessment Battery for Children, finger-tapping test, and Stroop numbers test. We conducted adjusted regression analyses to determine the association of pre-primary school attendance with test results and school progress. We found that pre-primary class enrollment was lower among children of female sex, Madheshi ethnicity, and low socioeconomic status. In adjusted analyses, pre-primary school enrollment was associated with beneficial scores on all cognitive tests. In addition, children who attended pre-primary school were less likely to repeat grade 1 (prevalence ratio 0.15, 95% CI 0.08-0.30, P < .001) or ever fail a grade (prevalence ratio 0.48, 95% CI 0.26-0.90, P = .02). In rural Nepal, there continue to be disparities in pre-primary school attendance; however, independent of these factors, pre-primary school attendance was associated with benefits in multiple cognitive domains and early school performance.

Physical Growth and Nonverbal Intelligence: Associations in Zambia

To investigate normative developmental body mass index (BMI) trajectories and associations of physical growth indicators--height, weight, head circumference (HC), and BMI--with nonverbal intelligence in an understudied population of children from sub-Saharan Africa. A sample of 3981 students (50.8% male), grades 3-7, with a mean age of 12.75 years was recruited from 34 rural Zambian schools. Children with low scores on vision and hearing screenings were excluded. Height, weight, and HC were measured, and nonverbal intelligence was assessed using the Universal Nonverbal Intelligence Test, Symbolic Memory subtest and Kaufman Assessment Battery for Children, Second Edition, Triangles subtest. Students in higher grades had a higher BMI over and above the effect of age. Girls had a marginally higher BMI, although that for both boys and girls was approximately 1 SD below the international Centers for Disease Control and Prevention and World Health Organization norms. When controlling for the effect of age, nonverbal intelligence showed small but significant positive relationships with HC (r = 0.17) and BMI (r = 0.11). HC and BMI accounted for 1.9% of the variance in nonverbal intelligence, over and above the contribution of grade and sex. BMI-for-age growth curves of Zambian children follow observed worldwide developmental trajectories. The positive relationships between BMI and intelligence underscore the importance of providing adequate nutritional and physical growth opportunities for children worldwide and in sub-Saharan Africa in particular. Directions for future studies are discussed with regard to maximizing the cognitive potential of all rural African children.

Associations between preterm birth, small-for-gestational age, and neonatal morbidity and cognitive function among school-age children in Nepal

BackgroundThe long term consequences of low birth weight (LBW), preterm birth, small-for-gestational age (SGA, defined as birth weight for given gestational age less than the 10th percentile of the reference), and early newborn morbidity on functional outcomes are not well described in low income settings.MethodsIn rural Nepal, we conducted neurocognitive assessment of children (n = 1927) at 7–9 y of age, for whom birth condition exposures were available. At follow-up they were tested on aspects of intellectual, executive, and motor function.ResultsThe prevalence of LBW (39.6%), preterm birth (21.2%), and SGA (55.4%) was high, whereas symptoms of birth asphyxia and sepsis were reported in 6.7% and 9.1% of children. In multivariable regression analyses, adjusted for confounders, LBW was strongly associated with scores on the Universal Nonverbal Intelligence Test (UNIT), tests of executive function, and the Movement Assessment Battery for Children (MABC). Preterm was not associated with any of the test scores. Conversely, SGA was significantly (all p < 0.005) associated with lower UNIT scores (−2.04 SE = 0.39); higher proportion failure on Stroop test (0.06, SE = 0.02); and lower scores on the backward digit span test (−0.16, SE = 0.04), MABC (0.98, SE = 0.25), and finger tapping test (−0.66, SE = 0.22) after adjusting for confounders. Head circumference at birth was strongly and significantly associated with all test scores. Neither birth asphyxia nor sepsis symptoms were significantly associated with scores on cognitive or motor tests.ConclusionIn this rural South Asian setting, intrauterine growth restriction is high and, may have a negative impact on long term cognitive, executive and motor function.

Cognitive and motor skills in school-aged children following maternal vitamin A supplementation during pregnancy in rural Nepal: a follow-up of a placebo-controlled, randomised cohort

ObjectiveTo determine the effects of maternal vitamin A supplementation from preconception through postpartum on cognitive and motor development of children at 10–13 years of age in rural Nepal.DesignFollow-up assessment of...

Associations between Preterm Birth, Small For Gestational Age, and Early Neonatal Morbidity, and Cognitive Function in School‐Age Children

The long term consequences of preterm, small for gestational age (SGA, defined as birth weight for given gestational age less than the 10th percentile of the reference), and early newborn morbidity on functional outcomes are not well described. In rural Nepal, we assessed children (n~1900) at 7–9 y of age, for whom these exposures were available at birth. The prevalence of low birth weight (LBW), preterm, and SGA was 40%, 21%, and 55%, respectively, whereas symptoms of birth asphyxia and sepsis were reported in 7% and 9% of children. At follow‐up they were tested on aspects of intellectual, executive, and motor function. In multivariable regression analyses, low birth weight was strongly associated with scores on the Universal Nonverbal Intelligence Test (UNIT), tests of executive function, and the Movement Assessment Battery for Children (MABC). However, of the two underlying causes of LBW, preterm was not associated with any of the test scores. However, SGA was significantly associated with lower UNIT scores (−1.9 SD=0.4); higher proportion failure on the Stroop test (0.06, SD=0.02); and lower scores on the backward digit span test (−0.14, SD=0.04), MABC (0.94, SD=0.27), and finger tapping test (−0.63, SD=0.23) (all p&lt;0.005). Neither birth asphyxia nor sepsis symptoms were significantly associated with the outcomes.Support: NICHD, Gates Foundation.

Preschool Iron-Folic Acid and Zinc Supplementation in Children Exposed to Iron-Folic Acid in Utero Confers No Added Cognitive Benefit in Early School-Age

In Nepal, antenatal iron-folic acid supplementation improved aspects of intellectual, executive, and fine motor function among school-age children. We examined the impact of added zinc to the maternal antenatal supplement (M-IFAZn) and preschool supplementation from 12 to 36 mo with iron-folic acid (C-IFA) ± zinc (C-IFAZn) on cognitive outcomes compared to maternal iron-folic acid (M-IFA) alone. Children 7–9 y old (n = 780) who participated in early childhood micronutrient supplementation trial during 2001–2004 and whose mothers participated in an antenatal micronutrient supplementation between 1999 and 2001 were followed for cognitive assessments in 2007–2009. Using multivariate analysis of variance and adjusting for confounders, M-IFA with child supplementation (either C-IFA or C-IFAZn) did not impact scores on the tests of general intelligence (Universal Nonverbal Intelligence Test), and executive function (Stroop and go/no go tests) relative to the M-IFA alone. However, children in the C-IFAZn group had slightly lower scores on the backward digit span (-0.29, 95% CI: -0.55, -0.04) and Movement Assessment Battery for Children (1.33, 95% CI: 0.26, 2.40) relative to the referent group, whereas both C-IFA (-1.92, 95% CI: -3.12, -0.71) and C-IFAZn (-1.78, 95% CI: -2.63, -0.92) produced somewhat lower finger tapping test scores (fine motor skills). The combination of M-IFAZn and C-IFA or C-IFAZn did not lead to any outcome differences relative to M-IFA alone. Preschool iron-folic acid ± zinc to children exposed to iron-folic acid in utero or addition of zinc to maternal iron-folic acid conferred no additional benefit to cognitive outcomes assessed in early school age. The late timing of supplementation during preschool may explain the lack of impact of iron and/or zinc.

Long‐term effects of micronutrient supplementation on intellectual and motor functions

Few data exist on long term consequences of micronutrient supplementation on cognitive/motor development. We examined cognitive/motor functioning of 7–9 y old Nepali children (n=694) who received micronutrient supplementation from 12–36 mo of age. In the initial study, children were randomized to daily iron-folic acid (IFA); zinc (Zn); iron-folic acid+zinc (IFAZn); placebo (PL). Follow-up outcomes were: Intellectual function (Universal Nonverbal Intelligence Test - UNIT), executive function (Go/no go, numbers Stroop test, and backward digit span), and motor function (Movement Assessment Battery for Children and a finger tapping test - FTT). Differences in test scores were examined relative to the PL for each supplementation group. In unadjusted analyses, children who received IFA and IFAZn did not score differently on any test compared to the PL group. Children who received Zn scored significantly better on the UNIT (3.03, 95%CI: 0.03, 6.03) and the FTT (2.17, 95%CI: −0.02, 4.37). They also had fewer % failures on the Stroop test (−0.18, 95%CI: −0.36, −0.01). In adjusted analyses, significantly fewer children in the IFA and Zn groups failed the Stroop test (−0.09, 95%CI: −0.17, −0.02 and −0.10, 95%CI: −0.16, −0.03, respectively). We conclude that zinc supplementation between 12–36 mo of age may have modest positive effects on aspects of executive functioning. Support: NICHD and Gates Foundation.

Preschool Iron‐Folic Acid and Zinc Supplementation in Children Exposed to Iron‐Folic Acid In Utero Confers No Added Cognitive Benefit in Early School‐age

Antenatal iron-folic acid supplementation improves aspects of intellectual, executive, and fine motor function among school-age offspring in rural Nepal. Using data from two RCTs, we examined whether combinations of added zinc to the maternal supplement (M-IFAZn) and preschool supplementation from 12–36 mo with iron-folic acid (C-IFA) +/− zinc (C-IFAZn) enhance cognitive outcomes beyond that seen with antenatal maternal iron-folic acid (M-IFA) alone. Relative to the M-IFA group, child supplementation did not impact scores on the UNIT (Universal Nonverbal Intelligence Test), Stroop and go/no go tests. However, children in the C-IFAZn group had lower scores on the backward digit span (adj −0.31, 95% CI: −0.59, −0.03) and movement assessment battery (adj 1.44, 95% CI: 0.20, 2.68). The combinations of C-IFA (−2.36, 95% CI: −4.14, −0.58), C-IFAZn (−1.92, 95% CI: −3.22, −0.63), and M-IFAZn/C-IFAZn (−2.04, 95% CI: −3.69, −0.44) produced lower finger tapping test scores after adjustment. Preschool iron-folic acid +/− zinc to children exposed to iron-folic acid in utero confers no additional benefit to cognitive outcomes assessed in early school age and may even diminish the positive effects of maternal iron-folic acid; mechanisms underlying this warrant investigation. Support: NICHD, Gates Foundation.

Prenatal Micronutrient Supplementation and Intellectual and Motor Function in Early School-aged Children in Nepal

Iron and zinc are important for the development of both intellectual and motor skills. Few studies have examined whether iron and zinc supplementation during gestation, a critical period of central nervous system development, affects children's later functioning. To examine intellectual and motor functioning of children whose mothers received micronutrient supplementation during pregnancy. Cohort follow-up of 676 children aged 7 to 9 years in June 2007-April 2009 who had been born to women in 4 of 5 groups of a community-based, double-blind, randomized controlled trial of prenatal micronutrient supplementation between 1999 and 2001 in rural Nepal. Study children were also in the placebo group of a subsequent preschool iron and zinc supplementation trial. Women whose children were followed up had been randomly assigned to receive daily iron/folic acid, iron/folic acid/zinc, or multiple micronutrients containing these plus 11 other micronutrients, all with vitamin A, vs a control group of vitamin A alone from early pregnancy through 3 months postpartum. These children did not receive additional micronutrient supplementation other than biannual vitamin A supplementation. Children's intellectual functioning, assessed using the Universal Nonverbal Intelligence Test (UNIT); tests of executive function, including go/no-go, the Stroop test, and backward digit span; and motor function, assessed using the Movement Assessment Battery for Children (MABC) and finger-tapping test. The difference across outcomes was significant (Bonferroni-adjusted P < .001) for iron/folic acid vs control but not for other supplement groups. The mean UNIT T score in the iron/folic acid group was 51.7 (SD, 8.5) and in the control group was 48.2 (SD, 10.2), with an adjusted mean difference of 2.38 (95% confidence interval [CI], 0.06-4.70; P = .04). Differences were not significant between the control group and either the iron/folic acid/zinc (0.73; 95% CI, -0.95 to 2.42) or multiple micronutrient (1.00; 95% CI, -0.55 to 2.56) groups. In tests of executive function, scores were better in the iron/folic acid group relative to the control group for the Stroop test (adjusted mean difference in proportion who failed, -0.14; 95% CI, -0.23 to -0.04) and backward digit span (adjusted mean difference, 0.36; 95% CI, 0.01-0.71) but not for the go/no-go test. The MABC score was lower (better) in the iron/folic acid group compared with the control group but not after adjustment for confounders (mean difference, -1.47; 95% CI, -3.06 to 0.12; P = .07). Finger-tapping test scores were higher (mean difference, 2.05; 95% CI, 0.87-3.24; P = .001) in the iron/folic acid group. Aspects of intellectual functioning including working memory, inhibitory control, and fine motor functioning among offspring were positively associated with prenatal iron/folic acid supplementation in an area where iron deficiency is prevalent. clinicaltrials.gov Identifier: NCT00115271.

Estudo das habilidades de memória e raciocínio simbólico e não-simbólico de crianças e adolescentes surdas por meio da bateria padrão do Universal Nonverbal Intelligence Test

Este estudo explorou as habilidades de memória e raciocínio simbólico e não simbólico de crianças e adolescentes com deficiência auditiva através das análises de desempenho da Bateria Padrão do Universal Nonverbal Intelligence Test (UNIT). Participaram deste estudo 55 crianças e adolescentes surdos. Os dados coletados foram analisados através de análises paramétricas. Os dados mostram que a memória simbólica, a capacidade de manipular e representar a informação simbólica memorizada está sendo melhorada por atividades escolares e/ou extracurriculares.

Effects of preconceptional through post‐partum vitamin A supplementation on intellectual, motor, and behavioural development of school‐aged offspring in rural Nepal.

Vitamin A deficiency in pregnancy is a common nutritional problem in poor countries, especially in South Asia. Moderate‐to‐severe vitamin A deficiency in pregnancy causes gestational night‐blindness, a risk factor for increased mortality in pregnancy and post‐partum. In rural Nepal a randomized, double‐blind, placebo controlled trial carried out from 1994 through 1997 showed that preconceptional through post‐partum weekly supplementation with vitamin A or beta‐carotene reduced maternal mortality by &gt;=40%, but had no effect on fetal loss, infant mortality, neonatal size or infant growth. Participants in this trial received a weekly dose of 7000 ug of retinol equivalents (RE) in an oil‐based capsule, approximating the RDA for pregnant or lactating women (~1000 ug RE). The weekly placebo capsule contained ~100 ug RE. The present study compared the development of peri‐adolescent children born to a subset of mothers randomized to receive vitamin A versus placebo during the trial. Trained assistants tested 381 ten to 13 year old children (mean age 12.3 years, 46% male) using the Universal Nonverbal Intelligence Test (UNIT) and the Movement Assessment Battery for Children (MABC) in local village test centers. Trained interviewers administered the Conners' Behavior Ratings to children's parents and teachers. Results to be presented will describe the treatment effect of vitamin A on the UNIT, MABC and Conners' Behavior Ratings, and also describe factors that predict test scores in this setting. Supported by the Bill and Melinda Gates Foundation, USAID, and the Sight and Life Research Institute.

Classifying Academically At-Risk First Graders into Engagement Types: Association with Long-Term Achievement Trajectories.

Based on a sample of 480 academically at-risk first graders, we used a cluster analysis involving multimethod assessment (i.e., teacher-report, peer-evaluation, and self-report) of behavioral and psychological engagement to identify subtypes of academic engagement. Four theoretically and practically meaningful clusters were identified and labeled as cooperative (n = 95), resistive (n =96), enthusiastic (n = 188), and disaffected (n = 101). The four types did not differ in IQ measured with the Universal Nonverbal Intelligence Test. The cooperative group consisted of more female and Hispanic students, whereas the resistive group consisted of more male and African American students. The cooperative group was the most popular among peers, followed by the enthusiastic group. The disaffected and resistive groups had more emotional symptoms than the cooperative and enthusiastic groups. Academic engagement types also differed in growth trajectories of academic achievement measured with Woodcock Johnson III Tests of Achievement from second to fourth grade. For reading, the cooperative and enthusiastic groups outperformed the resistive and disaffected groups at the beginning. However, the growth rate was similar across engagement types. For math, the engagement types did not differ at the beginning. However, the cooperative group developed at a faster rate and had higher math achievement by fourth grade than the other types. The findings support the importance of teaching temperament-based regulatory skills and of providing a positive psychological climate for children's academic learning.

Race Differences on the UNIT: Evidence from Multi-Sample Confirmatory Analysis

The Universal Nonverbal Intelligence Test (UNIT; Bracken & McCallum, 1998) is a standardized, norm referenced measure of intelligence in which administration and response formats are entirely nonverbal, requiring only universal hand gestures from the examiner and examinee. The UNIT was constructed in order to provide a more appropriate and valid assessment for children who are not fluent in a community’s dominant language and culture. Using multi-sample confirmatory factor analysis, the present study examines standardization for four different racial/ethnic groups (i.e., Whites, Blacks, Asians, and Hispanics), concluding that the observed differences in subtest performance are likely attributable to group differences in factor means. Suggestions for future study are offered.

Group Differences in Nonverbal Intelligence: Support for the Influence of Spearman’s g

The Universal Nonverbal Intelligence Test (UNIT; Bracken & McCallum, 1998) is standardized, norm referenced measure of that requires only universal hand gestures from the examiner and examinee. The UNIT was constructed in order to measure the cognitive abilities of children who may be disadvantaged by more traditional tests, which typically emphasize receptive and expressive language abilities. In the present study, standardization data from the UNIT is examined to identify group differences in performance. Despite its novel nonverbal format and response demands, group differences are identified. Subsequent analysis confirms the substantial influence of Spearman's g in explaining these observed group differences. Key Words: Intelligence; Nonverbal; Spearman's No practice in psychology has inspired or endured more criticism than mental testing. Usually, the strident attacks target the repeated finding that Blacks and Whites differ in varying degrees on tests of intellectual ability (Edwards & Oakland, 2006; Jensen, 1998; Naglieri J Rushton & Jensen, 2005). While researchers are in general consensus that these differences exist, there is considerable debate about their origin (Devlin, Feinberg, Resnick, & Roeder, 1997; Kamin, 1974; Miele, 1995, 2002). Generally, four explanations are offered to explain BlackWhite differences in measured cognitive abilities. First, group differences are the result of psychometric bias, such differential item functioning, reliability, or validity (Dolan, Roorda, & Wicherts, 2004; Jensen, 1980; 1981; 1998). second, measured group differences are not manifestations of per se, but rather they reflect the degree to which a minority group's culture and language differs from the majority. This sentiment is captured in Cole and Cole's statement that intelligence cannot be tested independently of the culture that gives rise to the test (1993, p. 502). Third, researchers attribute differences to broad factors or subtest specificity (e.g., spatial abilities). Jensen (1998) and others (e.g., Rushton, 1998; Rushton & Jensen, 2003) have substantiated that certain racial/ethnic groups differ in regard to particular broad abilities. However, the extant research consistently finds the influence of these broad abilities is meager, with combinations of these factors accounting for less than 10% of the between-group variance (Jensen, 2001). The fourth explanation is that group differences are a function of the demand a subtest places on general (Spearman's g). This last proposal has its provenance in The Abilities of Man (1927), Charles Spearman's treatise on the nature of intelligence. In describing the Black-White differences in IQ, Spearman (p. 379) advanced that group difference in IQ would be most marked in just those [tests] which are known to be saturated with g. Basically, Spearman's Hypothesis proposed that the magnitude of average Black-White differences in intellectual performance is related to the demand a subtest places on the general factor. As an example, one of the common activities on various IQ tests requires the examinee to repeat a series of digits that are read aloud. Usually, the examinee is required to recall the digits as they are presented initially (forward) or in reverse order (backward). Although the content is identical, these two cognitive activities require different amounts of mental manipulation of the input, with the recall of digits in reverse order clearly placing more demands on Spearman's g (Saltier, 2001). Typically for this task, Black-White differences in performance are reliably twice as large for the backward condition as for the forward condition (Jensen and Figueroa, 1975). …

Concurrent validity of the Universal Nonverbal Intelligence Test and the Leiter International Performance Scale–Revised

One hundred elementary- and middle-school students were administered the Universal Nonverbal Intelligence Test (UNIT; B.A. Bracken & R.S. McCallum, 1998) and the Leiter International Performance Scale-Revised (Leiter-R; G.H. Roid & L.J. Miller, 1997). Correlations between UNIT and Leiter-R scores were statistically significant ( p < .001), ranging from .33 to .74. The UNIT Full Scale score was 5 points higher than the Leiter-R Full Scale score, t = 4.73, p < .001. © 2006 Wiley Periodicals, Inc. Psychol Schs 43: 143–148, 2006.

Convergent and Discriminant Validity of the Universal Nonverbal Intelligence Test with Limited English Proficient Mexican-American Elementary Students

Correlations and mean score differences between IQs derived from the Universal Nonverbal Intelligence Test (UNIT; Bracken &amp; McCallum, 1998) and the Wechsler Intelligence Scale for Children-Third Edition (WISC-III; Wechsler, 1991) were compared. Participants were Limited English Proficient (LEP) Mexican-American elementary school students, who were administered the UNIT and the WISC-III in counterbalanced order. The data revealed greater than expected correlations between the UNIT Full Scale and the WISC-III Full Scale and Verbal IQs. Patterns of correlations between the UNIT and the WISCIII provided support for both the convergent and discriminant validity of the UNIT with the targeted population. As anticipated, UNIT Full Scale IQs were significantly higher than WISCIII Full Scale IQs.