Peabody Picture Vocabulary Test-Revised Scores Research Articles

Receptive Language Abilities for Females Exposed to Early Life Adversity: Modification by Epigenetic Age Acceleration at Midlife in a 30-Year Prospective Cohort Study.

Deviations from normative trajectories of receptive language abilities following early life adversity (ELA) may indicate an elevated risk for advanced cognitive aging and related morbidities. Accelerated epigenetic aging at midlife may further identify those at greatest risk for advanced cognitive aging following ELA. We examined whether accelerations in epigenetic aging at midlife can identify those individuals who demonstrated the greatest change in receptive language abilities following ELA. Data were drawn from the Female Growth and Development Study (n=86), a 30-year prospective cohort study of females exposed to substantiated child sexual abuse (CSA), a severe ELA, and a non-CSA comparison condition. The Peabody Picture Vocabulary Test-Revised (PPVT-R) measured receptive language abilities on 6 occasions from childhood to mid-life. Interindividual differences in PPVT-R trajectories were examined in relation to CSA exposure and across 5 independent measures of epigenetic age acceleration derived from first (Horvath DNAmAge, Hannum DNAmAge) and second (GrimAge, PhenoAge, Dunedin Pace of Aging) generation epigenetic clocks. Quadratic growth models revealed that PPVT-R scores were significantly lower at age 25 for females exposed to CSA. Specifically, CSA exposed females had lower intercepts when GrimAge was accelerated and a smaller quadratic trend when PhenoAge was accelerated. ELA is associated with significant differences in development of receptive language abilities with the most pronounced differences observed for females with accelerated epigenetic ages at mid-life. These findings suggest that epigenetic age acceleration could serve as an indicator of differences in cognitive aging and portend to later adulthood cognitive functioning.

Timing and Chronicity of Maternal Depression Symptoms and Children's Verbal Abilities

To test the associations between the timing and chronicity of maternal depression symptoms (MDS) and children's long-term verbal abilities. Participants were 1073 mother-child pairs from a population-based birth cohort in Canada. MDS were assessed at ages 5 months, 1.5, 3.5, and 5 years using the Center for Epidemiologic Studies Depression Scale. Verbal abilities were measured at 5, 6, and 10 years using the Peabody Picture Vocabulary Test-Revised (PPVT-R). Multiple linear regression models were used to estimate the association between timing (early: 5 months and/or 1.5 years vs late 3.5 and/or 5 years) and chronicity (5 months, 1.5, 3.5, and 5 years) of exposure to elevated MDS and children's mean PPVT-R scores. Children exposed to chronic MDS had lower PPVT-R scores than children never exposed (mean difference = 9.04 [95% CI = 2.28-15.80]), exposed early (10.08 [3.33-16.86]) and exposed late (8.69 [1.85-15.53]). There were no significant differences between scores of children in the early compared with the late exposure group. We adjusted for mother-child interactions, family functioning, socioeconomic status, PPVT-R administration language, child's birth order, and maternal IQ, psychopathology, education, native language, age at birth of child, and parenting practices. Maternal IQ, (η2 = 0.028), native language (η2 = 0.009), and MDS (η2 = 0.007) were the main predictors of children's verbal abilities. Exposure to chronic MDS in early childhood is associated with lower levels of verbal abilities in middle childhood. Further research is needed in larger community samples to test the association between MDS and children's long-term language skills.

Epilepsy, school readiness in Canadian children: Data from the National Longitudinal Study of Children and Youth (NLSCY)

PurposeUtilizing data from the National Longitudinal Survey of Children and Youth (NLSCY) we evaluated the association between childhood epilepsy and health impairments on measures of school readiness employed in the survey. MethodsStandard scores on the Peabody Picture Vocabulary Test-Revised (PPVT-R) were employed in a regression analysis to compare scores in children with and without epilepsy. We also examined the effect of impairments in any of the 8 domains of the Health Utilities index (HUI) on test scores. ResultsA total sample size of 39,130 children (20,044 males, and 19,086 female were included in the analysis, 33,560 children were administered the PPVT-R at a mean age of 4.5 years. There were 70 children with epilepsy, 21 had a score of 1 on the HUI, 21 were assessed to have a HUI<1 (signifying health impairments in one or more of the 8 domains). In the remainder, the PPVT scores were missing. Using the Ordinary Least Squares (OLS) regression for continuous outcomes model for PPVT-R scores as the outcome variable, females scored 1.1 points higher (β=1.1, 95%CI 0.755, 1.444, p=0.000), children without epilepsy and HUI score of <1 scored 3.84 points lower (β=−3.843 95%CI −4.232, −3.452, p=0.000). Children with epilepsy and a HUI score of 1 scored 9.90 points lower (β=−9.902, 95%CI −16.343, −3.461, p=0.003) while those with epilepsy and HUI<1 scored 17.30 lower (β=−17.308, 95%CI −23.776, −10.839, p=0.000). ConclusionThe data provide objective evidence that children with epilepsy are at risk of scholastic underachievement at school entry, while those with additional health impairments as measured by the HUI are at greater risk of underachievement.

Chinese Immigrant Families and Bilingualism Among Young Children

Thirty-five children (17 boys and 18 girls, 4 to 8 years old) in 2-parent Chinese immigrant families had attended English-speaking facilities for 35.0 months (boys) and 32.9 months (girls), respectively. They were tested at home with the Peabody Picture Vocabulary Test–Revised (PPVT-R) and the Mandarin version of PPVT-R. No gender differences were found. Maternal English PPVT-R vocabulary (M = 112.9) correlated positively with child PPVT-R scores (r = . 35, p = . 04). The longer the children attended English-only educational facilities, the higher were their English PPVT-R scores (r = .327, p = .059), even when controlling for maternal scores. Children (n = 12) who had spent about 2 years (22 to 26 months) in English-speaking educational facilities had English PPVT-R standardized scores (M = 94.8, range = 71–110) close to the average (M = 100) score of English monolinguals. Chinese receptive language scores increased during the preschool years and were normative with monolingual Chinese children until abo...

Do hypertensive diseases of pregnancy disrupt neurocognitive development in offspring?

The current study sought to determine whether hypertensive diseases of pregnancy (gestational hypertension and pre-eclampsia) are associated with neurocognitive outcomes in middle childhood. Participants were members of the Western Australian Pregnancy Cohort (Raine) Study. Data were available for 1389 children (675 females; mean age = 10.59 years; SD = 0.19). Twenty-five per cent of these participants were offspring of pregnancies complicated by either gestational hypertension (n = 279), or pre-eclampsia (n = 34). Verbal ability at age 10 years was assessed with the Peabody Picture Vocabulary Test - Revised (PPVT-R), and non-verbal ability with Ravens Colored Progressive Matrices (RCPM). Separate multivariable regression analyses, incorporating sociodemographic, antenatal, obstetric and postnatal covariates, investigated the effect of a two- (normotensive pregnancy vs. hypertensive pregnancy) and three-level (normotensive pregnancy vs. gestational hypertension vs. pre-eclampsia) predictor variable on PPVT-R and RCPM scores. Offspring of pregnancies complicated by maternal hypertension (gestational hypertension or pre-eclampsia) had a mean PPVT-R score that was 1.83 ([95% confidence interval (CI) -3.48, -0.17], P = 0.03) points lower than children from normotensive pregnancies. Multivariable regression analysis also identified a significant inverse association between the three-level predictor variable and offspring PPVT-R scores (P = 0.02). Gestational hypertension (without pre-eclampsia) reduced offspring PPVT-R scores by 1.71 points [95% CI -3.39, -0.03] and pre-eclampsia led to a reduction of 3.53 points [95% CI -8.41, 1.35], although this latter association did not achieve statistical significance. There was no effect of the two- (P = 0.99) or three-level (P = 0.92) predictor variable on RCPM scores. Maternal hypertensive diseases of pregnancy are a risk factor for a small reduction in offspring verbal ability.

Speech concerns at 5 years and adult educational and mental health outcomes

To determine if parent-reported speech concerns at 5 years predict poorer educational and mental health outcomes at 21 years independent of social context and child's receptive language, behaviour and motor concerns at 5 years. To determine if these adult outcomes are mediated by school performance at 14 years. Information on speech concerns at 5- and 21-year outcomes was available for 3193 participants from a birth cohort of 7223 infants. At 5, child behaviour was measured using a behavioural checklist, and at 21 years, it was measured by the Young Adult Self-Report. Peabody Picture Vocabulary Test-Revised at 5 years was not available for all children. Maternal mental health and social information at 5 years and educational outcomes at 14 years and 21 years were collected prospectively by questionnaire. Potential confounding and mediating factors were analysed using logistic regression. Children with speech concerns were less likely to have completed secondary school (P < 0.01) or gained better overall position (OP) scores (P < 0.001). OP scores rank students in Queensland applying for tertiary entrance. There was no association with mental health outcomes. Findings were independent of maternal and social factors, and motor concerns, though attenuated by behaviour and Peabody Picture Vocabulary Test-Revised scores. In the model adjusted for these factors, any concerns predicted OP score 1-11 (odds ratio 0.58; 95% confidence interval 0.42, 0.79), though if academic functioning at 14 was included, no associations were significant. Maternal-reported speech concerns at 5 years predict poorer educational though not adult mental health outcomes.

Duration of breast feeding and language ability in middle childhood

There is controversy over whether increased breast-feeding duration has long-term benefits for language development. The current study examined whether the positive associations of breast feeding on language ability at age 5 years in the Western Australian Pregnancy (Raine) Cohort, were still present at age 10 years. The Raine Study is a longitudinal study of 2868 liveborn children recruited at approximately 18 weeks gestation. Breast-feeding data were based upon information prospectively collected during infancy, and were summarised according to four categories of breast-feeding duration: (1) never breast-fed, (2) breast-fed predominantly for <4 months, (3) breast-fed predominantly for 4-6 months, and (4) breast-fed predominantly for >6 months. Language ability was assessed in 1195 children at the 10 year follow-up (mean age = 10.58 years; standard deviation = 0.19) using the Peabody Picture Vocabulary Test - Revised (PPVT-R), which is based around a mean of 100 and a standard deviation of 15. Associations between breast-feeding duration and PPVT-R scores were assessed before and after adjustment for a range of sociodemographic, obstetric and psychosocial covariates. Analysis of variance revealed a strong positive association between the duration of predominant breast feeding and PPVT-R at age 10 years. A multivariable linear regression analysis adjusted for covariates and found that children who were predominantly breast-fed for >6 months had a mean PPVT-R score that was 4.04 points higher than children who were never breast-fed. This compared with an increase of 3.56 points at age 5 years. Breast feeding for longer periods in early life has a positive and statistically-independent effect on language development in middle childhood.

School readiness and later achievement: Replication and extension using a nationwide Canadian survey.

In this article we replicate and extend findings from Duncan et al. (2007). The 1st study used Canada-wide data on 1,521 children from the National Longitudinal Survey of Children and Youth (NLSCY) to examine the influence of kindergarten literacy and math skills, mother-reported attention, and mother-reported socioemotional behaviors on 3rd-grade math and reading outcomes. Similar to Duncan et al., (a) math skills were the strongest predictor of later achievement, (b) literacy and attention skills predicted later achievement, and (c) socioemotional behaviors did not significantly predict later school achievement. As part of extending the findings, we incorporated a multiple imputation approach to handle missing predictor variable data. Results paralleled those from the original study in that kindergarten math skills and Peabody Picture Vocabulary Test-Revised scores continued to predict later achievement. However, we also found that kindergarten socioemotional behaviors, specifically hyperactivity/impulsivity, prosocial behavior, and anxiety/depression, were significant predictors of 3rd-grade math and reading. In the 2nd study, we used data from the NLSCY and the Montreal Longitudinal-Experimental Preschool Study (MLEPS), which was included in Duncan et al., to extend previous findings by examining the influence of kindergarten achievement, attention, and socioemotional behaviors on 3rd-grade socioemotional outcomes. Both NLSCY and MLEPS findings indicated that kindergarten math significantly predicted socioemotional behaviors. There were also a number of significant relationships between early and later socioemotional behaviors. Findings support the importance of socioemotional behaviors both as predictors of later school success and as indicators of school success.

Maternal life events during pregnancy and offspring language ability in middle childhood: The Western Australian Pregnancy Cohort Study

Background There is accumulating evidence for a link between maternal stress during pregnancy and later behavioural and emotional problems in children. Little research has examined other developmental outcomes. Aim To determine the effect of maternal stress during pregnancy on offspring language ability in middle childhood. Study design Longitudinal pregnancy cohort-study. Subjects A total of 2900 mothers were recruited prior to the 18th week of pregnancy, delivering 2868 live births. The language ability of just under half of the offspring cohort ( n = 1309; 45.6% of original sample) was assessed in middle childhood (Mean age = 10;7, Standard deviation = 0;2, range: 9;5–11;11). Outcome measures Language ability was measured using the Peabody Picture Vocabulary Test-Revised (PPVT-R). The main predictor variable was the frequency of 10 typically ‘stressful’ life events experienced by mothers during early and/or late pregnancy. Children were allocated to four groups according to whether they were exposed to high maternal stress (≥ 2 life events) during early pregnancy only, late pregnancy only, both, or neither. Results Mixed-effects regression analyses revealed no association between the maternal experience of two or more stressful life events at any time-point during pregnancy and PPVT-R scores. Repeating the regression analyses with more lenient (≥ 1 life events) or strict (≥ 3 life events) thresholds for defining high-levels of maternal stress did not alter the pattern of findings. Conclusions Maternal experience of typically stressful life events during pregnancy has a negligible effect on vocabulary development to middle childhood.

Functional connectivity to a right hemisphere language center in prematurely born adolescents

Prematurely born children are at increased risk for language deficits at school age and beyond, but the neurobiological basis of these findings remains poorly understood. Thirty-one PT adolescents (600–1250g birth weight) and 36 T controls were evaluated using an fMRI passive language task and neurodevelopmental assessments including: the Wechsler Intelligence Scale for Children-III (WISC-III), the Peabody Picture Vocabulary Test-Revised (PPVT-R), the Comprehensive Test of Phonological Processing (CTOPP) and the Test of Word Reading Efficiency (TOWRE) at 16years of age. Neural activity was assessed for language processing and the data were evaluated for connectivity and correlations to cognitive outcomes. PT subjects scored significantly lower on all components of the WISC-III (p<0.05) compared to term subjects, but there was no significant difference in PPVT-R scores between the groups. Functional connectivity (fcMRI) between Wernicke's area (left BA 22) and the right supramarginal gyrus (BA 40) was increased in preterm subjects relative to term controls (p=0.03), and the strength of this connection was inversely related to performance on both the PPVT-R (R2=0.553, p=0.002), and the verbal comprehension index (R2=0.439, p=0.019). Preterm adolescents engage a dorsal right hemisphere region for language at age 16years. Those with the greatest cognitive deficits demonstrate increasing reliance on this alternate pathway.

How well do poor language scores at ages 3 and 4 predict poor language scores at age 6?

The purpose of this study was to describe findings and associations at the group level, and predictive accuracy at the individual level, for three measures of language obtained from a single prospective cohort of US children assessed at three ages during another investigation. Participants comprised all children (n = 414) who had a score at each of three ages (3, 4, and 6 years) on three language measures: Peabody Picture Vocabulary Test-Revised (PPVT); mean length of utterance in morphemes (MLU); and total percentage of phonemes correct (TOTPPC) in a nonword repetition task. At the group level, mean differences and correlations over ages were calculated. At the individual level, the extent to which low scores (1.5 SDs or more below the sample mean) at an earlier age increased the relative risk (R’) of low scores at a later age was calculated. At the group level, scores on all measures increased significantly with age. Earlier and later scores on each measure were significantly correlated; r2 values were generally modest (12–59%). A low score at age 3 did not increase the risk of a low score age 4 or age 6 for any of the measures; a low PPVT score at age 4 significantly increased the risk (R’ = 5.0) of a low PPVT score at age 6. For these generally healthy children and these language measures, predictive accuracy at the individual level was generally poor between the ages of 3, 4, and 6 years. Large, longitudinal studies are needed to identify and validate measures for use in identifying preschool children at risk for later language deficits.

Prematurely Born Children Demonstrate White Matter Microstructural Differences at 12 Years of Age, Relative to Term Control Subjects: An Investigation of Group and Gender Effects

The goal was to use diffusion tensor imaging to test the hypothesis that prematurely born children demonstrate long-term, white matter, microstructural differences, relative to term control subjects. Twenty-nine preterm subjects (birth weight: 600-1250 g) without neonatal brain injury and 22 matched, term, control subjects were evaluated at 12 years of age with MRI studies, including diffusion tensor imaging and volumetric imaging; voxel-based morphometric strategies were used to corroborate regional diffusion tensor imaging results. Subjects also underwent neurodevelopmental assessments. Neurodevelopmental assessments showed significant differences in full-scale, verbal, and performance IQ and Developmental Test of Visual Motor Integration scores between the preterm and term control subjects. Diffusion tensor imaging studies demonstrated widespread decreases in fractional anisotropy (a measure of fiber tract organization) in the preterm children, compared with the control subjects. Regions included both intrahemispheric association fibers subserving language skills, namely, the right inferior frontooccipital fasciculus and anterior portions of the uncinate fasciculi bilaterally, and the deep white matter regions to which they project, as well as the splenium of the corpus callosum. These changes in fractional anisotropy occurred in subjects with significant differences in frontal, temporal, parietal, and deep white matter volumes. Fractional anisotropy values in the left anterior uncinate correlated with verbal IQ, full-scale IQ, and Peabody Picture Vocabulary Test-Revised scores for preterm male subjects. In addition, preterm male subjects were found to have the lowest values for fractional anisotropy in the right anterior uncinate fasciculus, and fractional anisotropy values in that region correlated with both verbal IQ and Peabody Picture Vocabulary Test-Revised scores for the preterm groups; these findings were supported by changes identified with voxel-based morphometric analyses. Compared with term control subjects, prematurely born children with no neonatal ultrasound evidence of white matter injury manifest changes in neural connectivity at 12 years of age.

Association between nonmaternal care in the first year of life and children's receptive language skills prior to school entry: the moderating role of socioeconomic status

Studies have suggested that nonmaternal care (NMC) may either carry risks or be beneficial for children's language development. However, few tested the possibility that NMC may be more or less protective for children with different family backgrounds. This study investigates the role of the family environment, as reflected in the socioeconomic status (SES), in the association between NMC in the first year of life and children's receptive language skills prior to school entry. A representative sample of 2,297 Canadian children aged between 0 and 11 months at their first assessment was followed over 4 years. Receptive language skills were assessed with the Peabody Picture Vocabulary Test Revised (PPVT-R) when the child was 4 to 5 years old. After controlling for selection factors, SES was found to moderate the association between NMC and receptive language skills: Full-time NMC in the first year of life was associated with higher PPVT-R scores among children from low SES families (d = .58), but not among children from adequate SES families. Full-time NMC in infancy may contribute to reducing the cognitive inequalities between children of low and adequate SES.

A Functional Magnetic Resonance Imaging Study of the Long-term Influences of Early Indomethacin Exposure on Language Processing in the Brains of Prematurely Born Children

Previous studies have demonstrated that indomethacin lowers the incidence and decreases the severity of intraventricular hemorrhage, as well as improves the cognitive outcome, in prematurely born male infants. The purpose of this work was to use functional magnetic resonance imaging to test the hypothesis that neonatal indomethacin treatment would differentially affect brain activation across genders in school-aged, prematurely born children during performance of a language task. Forty-seven prematurely born children (600-1250-g birth weight) and 24 matched term control subjects were evaluated using a functional magnetic resonance imaging passive language task and neurodevelopmental assessments that included the Wechsler Intelligence Scale for Children-III and the Peabody Picture Vocabulary Test-Revised. Neural activity was assessed during both phonologic and semantic processing in the functional magnetic resonance imaging protocol. Neurodevelopmental assessments demonstrated significant differences in full-scale, verbal, and performance intelligence quotient, as well as Peabody Picture Vocabulary Test scores, between the preterm and term control subjects. Rates of perinatal complications did not differ significantly across preterm treatment groups, but male preterm subjects randomly assigned to saline tended to have lower Peabody Picture Vocabulary Test-Revised scores than did all of the other preterm groups. During phonological processing, a significant treatment-by-gender effect was demonstrated in 3 brain regions: the left inferior parietal lobule, the left inferior frontal gyrus (Broca's area), and the right dorsolateral prefrontal cortex. These data demonstrate a differential effect of indomethacin administration early in postnatal life on the subsequent development of neural systems that subserve language functioning in these male and female preterm infants.

Change in cognitive function over time in very low-birth-weight infants.

Preterm very low-birth-weight (VLBW) infants have a high prevalence of neurodevelopmental disability when evaluated during the first several years of life. However, recent experimental data suggest that the developing brain may recover from or compensate for injury. To determine if there is cognitive improvement throughout early and middle childhood following VLBW birth. Follow-up data of 296 infants born weighing 600 to 1250 g who participated in a prospective, randomized, placebo-controlled intraventricular hemorrhage (IVH) prevention study performed at 3 northeastern US hospitals between September 1989 and August 1992 and who were serially evaluated at 36, 54, 72, and 96 months of corrected age (CA). The age-normed Peabody Picture Vocabulary Test-Revised (PPVT-R) score and measures of intelligence. Overall, the median PPVT-R score increased from 88 at 36 months of CA to 99 at 96 months of CA; when data from 36 and 96 months of CA were compared, 45% of children gained 10 points or more and 12.5% showed a 5- to 9-point increase in test scores. Similar findings were noted for full-scale and verbal IQ scores. Multivariate analyses demonstrated that increasing age, residence in a 2-parent household, and higher levels of maternal education were all significantly associated with higher PPVT-R scores (for each, P<.001). In addition, early intervention led to greater increases over time in PPVT-R scores among children whose mothers had less than a high school education compared with those with a high school education level or greater (P =.03 by test for interaction). Although most children showed improvement in PPVT-R scores with increasing CA, children with early-onset IVH and subsequent significant central nervous system injury had the lowest PPVT-R scores initially and the scores declined over time (P =.009 by test for interaction). The majority of VLBW children had improvement in verbal and IQ test scores over time. Only children with early-onset IVH followed by significant central nervous system injury had low PPVT-R scores that declined over time.

The effect of breastfeeding on child development at 5 years: a cohort study.

It is uncertain to what degree the relationship between breastfeeding and later cognitive development is a true biological effect, or is confounded by psychosocial factors. The study aim was to further investigate this relationship and the effect of duration of breast feeding on cognitive development. A total of 3880 children were followed from birth. Breastfeeding duration was measured by questionnaire at 6 months of age and a Peabody Picture Vocabulary Test Revised (PPVT-R) was administered at 5 years. PPVT-R scores were adjusted for the effects of a large array of biological and psychosocial confounders. The relationship between breastfeeding and the mean PPVT-R scores were examined using analysis of variance and multiple linear regression. A strong positive relationship was demonstrated between breastfeeding and the PPVT-R scores with increasing scores with increased duration of breastfeeding. After adjusting for a wide range of biological and social factors, the adjusted mean for those breastfed for 6 months or more was 8.2 points higher for females and 5.8 points for males when compared to those never breastfed. These findings suggest a significant benefit to child development is conferred by breastfeeding and is related independently to longer periods of breastfeeding.

Behavioural and cognitive associations of short stature at 5 years.

To determine the extent to which childhood short stature is associated with cognitive, behavioural and chronic health problems, and whether these problems could be attributed to recognized adverse biological, psychosocial or psychological factors. At their first antenatal session, 8556 women were enrolled in a prospective study of pregnancy. When their children were 4 and 6 years of age, mothers completed a detailed questionnaire concerning their child's health and behaviour. A Peabody Picture Vocabulary Test-Revised (PPVT-R) was completed by the child at 5 years of age. Z scores were used to categorize height measurements in 3986 children. The relationship of these height categories with the child's health, and behavioural and cognitive problems was then examined. No association was found between height and symptoms of chronic disease or behaviour problems in boys or girls. On the unadjusted analysis, mean PPVT-R scores were significantly lower in boys with heights < 3 percentile and 3-< 10 percentile compared with study children between 10 to 90 percentile (P < 0.01). Scores were similarly significantly lower in girls with heights < 3 percentile and 3-10 percentile (P = 0.01). Even after adjusting for psychosocial and biological confounders, short stature remained a significant predictor for lower PPVT-R scores in both boys and girls, although height only accounted for 1.1% of the variance in scores in boys and 0.5% of the variance in PPVT-R scores in girls. Psychosocial factors had a greater role than height in determining PPVT-R scores at 5 years of age. These findings suggest a significant, though small, association between height and PPVT-R scores at 5 years of age, independent of psychosocial disadvantage and known biological risk factors.

The development of children's theory of mind: The working memory explanation

The hypothesis that a growth in working memory capacity could explain the observed development of theory of mind in preschoolers was tested. Fifty-four 3- to 5-year-olds were administered: two false belief tasks as measures of theory of mind development; two “false” photograph tasks parallel to typical false belief tasks, but involving nonmental representations; the Peabody Picture Vocabulary Test -Revised (PPVT-R); and two working memory capacity measures (backward digit span, BDS, and forward digit span, FDS). A multiple linear regression analysis revealed that BDS significantly predicted performance on both the false belief and false photograph tasks with age and PPVT-R score controlled, but that FDS did not, suggesting that growth in central executive capacity is important in determining children's success or failure on false belief tasks, but that articulatory loop capacity is not. It is concluded that, in general, the findings are consistent with the working memory hypothesis, although subsequent contingency table analysis revealed that success on the BDS task was not necessary for successful performance on theory of mind tasks.

Relationship between Wechsler scales and Peabody Picture Vocabulary Test-Revised scores among disability applicants

Relationships, including age, race, gender, and IQ level, between the Wechsler intelligence scales (WISC-R, WAIS-R) and the Peabody Picture Vocabulary Test-Revised (PPVT-R) were studied among 206 applicants for disability benefits in a private practice setting. We found that the PPVT-R seriously underestimated WISC-R IQs by an average of 5 points and WAIS-R IQs by an average of 12 points. Results were discussed in terms of psychometric findings and clinical application. The study demonstrates that psychologists in private practice settings can use the product of their daily work to address important questions that require empirical answers, which, in turn, can influence clinical practice.

Comparison of the PPVT-R and WAIS-R in state hospital psychiatric patients.

This study examined the relationship between the Peabody Picture Vocabulary Test-Revised (PPVT-R) and Wechsler Adult Intelligence Scale-Revised (WAIS-R) in 40 adult psychiatric inpatients. The tests were administered to the patients in counterbalanced order as part of their overall psychological evaluation. Mean scaled scores were obtained for both tests. There were no significant differences between PPVT-R scores and WAIS-R Verbal, Performance, and Full Scale IQ scores. Significant correlations between the PPVT-R and all three WAIS-R scores also were obtained. However, further analysis indicated a great deal of variability between individual PPVT-R and WAIS-R Full Scale scores. In addition, the PPVT-R was found to underestimate significantly the WAIS-R IQ scores of a subgroup (N = 13) of mildly mentally retarded subjects. A tendency for the PPVT-R to overestimate the WAIS-R as IQ improved also was noted.