McCarthy General Cognitive Index Research Articles

Expressive and receptive language functioning in preschool children with prenatal cocaine exposure.

To estimate the relationship between severity of prenatal cocaine exposure and expressive and receptive language skills in full-term, African American children at age 3 years. Language was assessed at age 3 using the Clinical Evaluation of Language Fundamentals-Preschool (CELF-P). The sample included 424 children (226 cocaine exposed, 198 non-cocaine exposed) who received preschool language assessments at age 3, drawn from a cohort of 476 children enrolled prospectively at birth. Structural equation modeling was used to regress expressive and receptive language as intercorrelated response variables on level of prenatal cocaine exposure, measured by a latent construct including maternal self-report of cocaine use and maternal/infant urine toxicology assays and infant meconium. Results indicated a.168 SD decrease in expressive language functioning for every unit increase in exposure level (95% CI = -.320, -.015; p =.031) after consideration for fetal growth and gestational age as correlated response variables. Receptive language was more modestly related to prenatal cocaine exposure and was not statistically significant. Results for expressive language remained stable with inclusion of the McCarthy general cognitive index as a response variable (expressive language beta = -.173, 95% CI = -.330, -.016; p =.031), and with adjustment for maternal age and prenatal exposures to alcohol, tobacco, and marijuana (expressive language beta = -.175, 95% CI = -.347, -.003; p =.046). Additional child and caregiver environmental variables assessed at age 3 were also evaluated in varying statistical models with similar results. The evidence from this study supports a gradient relationship between increased level of prenatal cocaine exposure and decreased expressive language functioning in preschool-aged cocaine-exposed children.

Effect of high maternal blood phenylalanine on offspring congenital anomalies and developmental outcome at ages 4 and 6 years: the importance of strict dietary control preconception and throughout pregnancy

Objectives The Maternal Phenylketonuria Study was designed to determine the effect of a phenylalanine (Phe)-restricted diet in reducing the morbidity on the fetus. Congenital abnormalities were noted, with the focus on the effect of congenital heart defects (CHDs) and microcephaly (MICRO) on developmental outcome at 4 and 6 years of age. Study design Women with blood Phe levels >240 μmol/L (n = 526; to convert μmol/L to mg/dL, divide by 60) were enrolled; 382 contributed 572 pregnancies. The women had 413 offspring examined at birth and annually. At 4 years, the McCarthy General Cognitive Index was administered, and at 6 years, the Wechsler Intelligence Scale for Children Revised was administered. Results Microcephaly was noted in 137 (33%) of the offspring, and 32 (7.7%) had CHD. Maternal blood Phe levels were higher for infants with CHD and MICRO than for infants with CHD only ( P = .02). Mean Phe levels at 4 to 8 weeks gestation predicted CHD ( P<.0001). The McCarthy General Cognitive Index score was lower with CHD ( P = .005) and MICRO ( P = .0017), as was the Wechsler Intelligence Scale for Children Revised full-scale IQ score ( P = .0002 for CHD and P = .0001 for MICRO). None of the subjects who had offspring with CHD had Phe control between 120 and 360 μmol/L during the first 8 to 10 weeks of gestation. Conclusions Women with phenylketonuria need to be educated regarding diet for life. This should help improve diet control before conception and throughout pregnancy.

Assessment of parental sensitivity towards pre‐school children born with very low birth weight

The article introduces the Parental Sensitivity Assessment Scale (PSAS) and examines the influence of the PSAS score and other factors on the general cognitive level in pre-school children born with very low birth weight (VLBW). McCarthy general cognitive index (GCI) was obtained for 102 VLBW and 92 normal birth weight (NBW) control children in Denmark in the mid-1980s. The mean ages of the two groups were 52.4 vs. 53.1 months. Parental sensitivity was assessed using PSAS. There was no significant difference in the mean PSAS score between the two birth weight groups (p > 0.3). Birth weight group (p < 0.001) and mother's schooling (p= 0.026) significantly correlated with GCI in the children. The PSAS score was highly significantly correlated to the variance of the GCI (p < 0.001), which was not explained by VLBW and mother's schooling. We found no interactional effect between parental sensitivity and birth weight group (p > 0.5) - the prematurely born children were not more affected by low parental sensitivity than were the control children.

Manganese, Monoamine Metabolite Levels at Birth, and Child Psychomotor Development

Several studies have demonstrated neurobehavioral impairment related to manganese (Mn) exposure in the workplace. Exposure to high doses of manganese is associated with irreversible neurodegenerative disorders resembling idiopathic Parkinson disease. Although there is a risk of Mn accumulation in the foetus during pregnancy, little information exists about developmental effects of environmental low-level exposure in human. For this reason, we conducted a prospective epidemiological study in 247 healthy pregnant women and their babies to determine the long-term effect of in utero Mn levels on child’s psychomotor development. Concurrently, we examined the relationship between Mn tissue levels at delivery and foetal plasma monoamine metabolites. Of the newborns, 195 were examined at 9 months, 126 at 3 years and 100 at 6 years. At 9 months, the Brunet–Lézine scales were administered. The McCarthy scales of children’s abilities were used at 3 and 6 years. After adjustment for potential confounding co-factors (child’s gender, mother’s educational level), negative relationships were observed between cord blood Mn levels and several psychomotor sub-scales at age of 3 years: “attention” (partial r=−0.33, P<0.001), “non-verbal memory” (partial r=−0.28, P<0.01), and “hand skills” (partial r=−0.22, P<0.05). No significant relationships were observed between Mn measures at birth and the general psychomotor indices, Brunet–Lézine developmental quotient (DQ) at 9 months or McCarthy general cognitive index (GCI) at 3 and 6 years. Maternal blood Mn levels were negatively associated with foetal plasma HVA and 5-HIAA concentrations (adjusted for labour duration, child’s gender, and smoking during pregnancy), but the adjustment for monoamine levels at birth did not change the association between the Mn levels and the psychomotor scores. These results suggest that environmental Mn exposure in utero could affect early psychomotor development.

The Validity of a Parent-based Assessment of Cognitive Abilities in Three-year Olds*

The purpose of the present study was to validate a parent-based assessment of cognitive abilities of three-year-old children against a standard tester-administered measure. The cognitive abilities of 85 children (50 boys and 35 girls, members of 43 twin pairs) were assessed using a measure of non-verbal abilities called the Parent Report of Children's Abilities for three-year-olds (PARCA3), a vocabulary checklist, and the McCarthy Scales of Children's Abilities (McCarthy, 1972). Correlations indicated that both components of the PARCA3 (parent-report and parent-administered) were significantly associated with the McCarthy scales, as was the vocabulary measure. Most importantly, the PARCA3 and vocabulary measure in combination significantly and substantially predict the McCarthy General Cognitive Index (Total R =0.63). We conclude that the PARCA3, with the vocabulary measure, provides a valid, inexpensive, reliable measure of cognitive ability for very young children.

Association between Methylmercury Exposure from Fish Consumption and Child Development at Five and a Half Years of Age in the Seychelles Child Development Study: An Evaluation of Nonlinear Relationships

Studies to date of the developmental effects of pre- and postnatal methylmercury exposure from fish consumption in the Seychelles Islands, using linear regression models for analysis, have not shown adverse effects on neurodevelopmental test scores. In this study we evaluated whether nonlinear effects of methylmercury exposure were present, using scores on six tests administered to cohort children in the Seychelles Child Development Study at 66 months of age. Prenatal exposure was determined by measuring mercury in a segment of maternal scalp hair representing growth during pregnancy. Postnatal exposure was measured in a segment of the child's hair taken at 66-months of age. Generalized additive models (GAMs), which make no assumptions about the functional form of the relationship between exposure and test score, were used in the analysis. GAMs similar to the original linear regression models were used to reanalyze the six primary developmental endpoints from the 66-month test battery. Small nonlinearities were identified in the relationships between prenatal exposure and the Preschool Language Scale (PLS) Total score and Child Behavior Check List (CBCL) and between postnatal exposure and the McCarthy General Cognitive Index (GCI) test scores. The effects are best described graphically but can be summarized by computing the change in the predicted test score from 0 to either 10 or 15 ppm and then above this point. For the PLS the trend involved a decline of 0.8 points between 0 and 10 ppm followed by an increase (representing improvement) of 1.3 points above 10 ppm. For the CBCL there was an increase of 1 point from 0 to 15 ppm, and then a decline (improvement) of 4 points above 15 ppm. The GCI increased by 1.8 points through 10 ppm and then declined 3.2 points (representing worse performance) above 10 ppm. These results are not entirely consistent. Two of the trends involve what appear to be beneficial effects of prenatal exposure. The one possibly adverse trend involves postnatal exposure. In every case the trend changes direction, so that an effect in one direction is followed by an effect in the opposite direction. Because of the descriptive nature of GAMs it is difficult to provide a precise level of statistical significance for the estimated trends. Certainly above 10 ppm there is less data and trends above this level are estimated less precisely. Overall there was no clear evidence for consistent (across the entire range of exposure levels) adverse effects of exposure on the six developmental outcomes. Further nonlinear modeling of these data may be appropriate, but there is also the risk of fitting complex models without a clear biological rationale.

Outcome at age 4 years in offspring of women with maternal phenylketonuria: the Maternal PKU Collaborative Study.

Untreated maternal phenylketonuria (PKU) increases risk for developmental problems in offspring. The extent to which this risk is reduced by maternal dietary therapy at various stages of pregnancy is not known. To determine whether dietary treatment during pregnancy of women with PKU affects developmental outcomes of offspring. The Maternal PKU Collaborative Study, an ongoing, longitudinal prospective study begun in 1984. A total of 78 metabolic clinics and obstetrical offices in the United States, Canada, and Germany. A total of 253 children of women with PKU (n = 149), with untreated mild hyperphenylalaninemia (n = 33), or without known metabolic problems (comparison group; n = 71) were followed up to age 4 years. Women with PKU were offered a low-phenylalanine diet prior to or during pregnancy with the aim of maintaining metabolic control (plasma phenylalanine < or =10 mg/dL [< or =605 micromol/L]). Women with mild hyperphenylalaninemia, who had plasma phenylalanine levels of no more than 10 mg/dL (605 micromol/L) on a normal diet, were not treated. Children's scores on cognitive and behavioral assessments (McCarthy Scales of Children's Abilities, Test of Language Development, Achenbach Child Behavior Checklist, Vineland Adaptive Behavior Scales, and Home Observation for Measurement of the Environment), compared by maternal metabolic status at 0 to 10 weeks', 10 to 20 weeks', and after 20 weeks' gestation. Scores on the McCarthy General Cognitive Index decreased as weeks to metabolic control increased (r = -0.58; P<.001). Offspring of women who had metabolic control prior to pregnancy had a mean (SD) score of 99 (13). Forty-seven percent of offspring whose mothers did not have metabolic control by 20 weeks' gestation had a General Cognitive Index score 2 SDs below the norm. Overall, 30% of children born to mothers with PKU had social and behavioral problems. Our data suggest that delayed development in offspring of women with PKU is associated with lack of maternal metabolic control prior to or early in pregnancy. Treatment at any time during pregnancy may reduce the severity of delay.

Developmental Catch‐up, and Deficit, Following Adoption after Severe Global Early Privation

The extent of developmental deficit and catch‐up following adoption after severe global early privation was examined at 4 years in a sample of 111 Romanian children who came to the U.K. before the age of 2 years, and compared with respect to their functioning at the same age to a sample of 52 U.K. adopted children placed before the age of 6 months. The measures at 4 years included height, head circumference, and general cognitive level (assessed on both the McCarthy and Denver Scales). The children from Romania were severely developmentally impaired at the time of U.K. entry, with about half below the third percentile on height, on weight, on head circumference, and on developmental quotient. Many were also in a poor physical state with recurrent intestinal and respiratory infections. The catch‐up in both physical growth and cognitive level appeared nearly complete at 4 years for those children who came to the U.K. before the age of 6 months, despite the fact that their background prior to U.K. entry was similar to the children who came to the U.K. when older. The developmental catch‐up was also impressive, but not complete, in those placed after 6 months of age. The mean McCarthy General Cognitive Index was 92 compared with 109 for the within‐U.K. adoptees. The strongest predictor of level of cognitive functioning at 4 years was the children's age at entry to the U.K. It was concluded that the remaining cognitive deficit was likely to be a consequence of gross early privation, with psychological privation probably more important than nutritional privation. A further follow‐up at age 6 years will determine whether there is continuing recovery after 4 years.

Cognitive Referencing as a Method of OT/PT Triage for Young Children

Cognitive referencing predicts that children with significant motor delays commensurate with their cognitive abilities will benefit from physical therapy and/or occupational therapy to a lesser degree than children with cognitive abilities, which are significantly higher than their motor abilities. This paper examines the key prediction of the cognitive referencing triage model: that IQ is a strong predictor of response to treatment. Thirty-nine children (three to six years old) with motor delays were divided into two groups (high IQ and low IQ) based on the McCarthy General Cognitive Index. All children received occupational therapy or physical therapy for nine months. Participants were posttested using the Peabody Developmental Motor Scales at the end of the school year to determine motor gains. Between-group comparisons, using repeated measures analysis of variance with time as a within-group factor and group (low IQ, high IQ) as a between-subjects factor, revealed no significant differences in Peabody Developmental Motor Scales z scores between groups. These results do not support the cognitive referencing model. Implications, including the potential for the cognitive referencing model to inappropriately exclude motor-delayed children from occupational therapy/physical therapy services, are discussed.

Neurodevelopmental outcome in very low birth weight infants at 24 months and 5 to 7 years of age: Changing diagnosis

We describe the long-term development of 53 very low birth weight premature infants. The children were divided into 2 groups on the basis of ultrasound scan, and classified as: group 1, patients with normal ultrasound scan or with uncomplicated hemorrhage; and group II patients with complicated hemorrhage or only parenchymal lesions. Minor and major sequelae detected at 2 years of age were compared with those observed at 5 to 7 years. Our study confirms that most severely handicapped children are identified by age 2 years. Minor sequelae are more evident at 5 to 7 years and subjects with good outcome, as expressed by a McCarthy General Cognitive Index score > 80, present a discordant cognitive profile with verbal scores higher than performance scores. Therefore, we emphasize the importance of follow-up of very low birth weight premature infants until school age and stress that neonatal ultrasound scan diagnosis of parenchymal damage represents an important diagnostic tool in terms of both short- and long-term neurodevelopmental outcome.

Antenatal Phenobarbital Therapy and Neonatal Outcome II: Neurodevelopmental Outcome at 36 Months

To evaluate the effect of antenatal phenobarbital (PB) therapy on neurodevelopmental outcome at 36 months. Prospective, randomized, controlled trial. Single-institution study. SUBJECT AND INTERVENTIONS: Children born to women who participated in the study evaluating the effect of antenatal phenobarbital (PB) on neonatal intracranial hemorrhage were prospectively followed to 3 years of age. Physical growth, neurologic examinations, and developmental testing (McCarthy Scales of Children's Abilities). Comparisons between groups were made on all children and those born to multiple gestations. Forty-one children born to women who received 10 mg/kg PB before delivery and 55 children in the control group were evaluated. Three children, all in the control group, had growth parameters (height, weight, and head circumference) below the fifth percentile. The McCarthy General Cognitive Index (standard, 100 +/- 16) was 93 +/- 20 in the PB group and 85 +/- 18 in the control group. The subscores tended to be higher in the PB group than in the control group, with higher quantitative scores in the PB group (44 +/- 11 vs 39 +/- 8). Neurologic deficits were noted in 2 of 41 in the PB group and in 6 of 55 in the control group. Infants born to women who received antenatal PB therapy had similar neurodevelopmental outcomes as infants born to women who did not receive PB. No adverse effects of PB exposure were detected.

School-Age Follow-Up of A Single-Dose Prophylactic Surfactant Cohort

This study reports the school-age developmental and health status of a preventilatory surfactant cohort. The sample consisted of 39 surviving subjects (21 experimental and 18 controls) born at 25 to 29 weeks gestation who were studied at 6 and 12 months and 5 to 7 years of age. At 6- and 12-month follow-ups, the cohort was functioning close to the population normative mean. Although cognitive and motor assessments at school age also showed no group differences, 8 of 19 (42%) in the surfactant group and 9 of 17 (53%) in the normal saline group attained a McCarthy General Cognitive Index score of < or = 84 (abnormal range). On the Connors' Parental Questionnaire, both groups scored high on the Learning Disability Subscale. The surviving cohort at 5 to 7 years had no identified long-term sequelae due to surfactant therapy, yet both groups were at risk for neurodevelopmental and educational morbidity.

Neuropsychological Effects of Cranial Irradiation in Young Children With Acute Lymphoblastic Leukemia 9 Months After Diagnosis

To determine the effects of cranial irradiation on neuropsychological test performance evident 9 months after diagnosis. A companion study to a randomized clinical trial (CCG-105). Institutions participating in Childrens Cancer Group cooperative treatment trials. Seventy-four children aged 3.0 to 6.5 years with average-risk acute lymphoblastic leukemia. Children with central nervous system leukemia at the time of diagnosis, preexisting mental retardation, or Down's syndrome or for whom English was not the primary language were not eligible for study. Children were randomized to receive treatment with one of four systemic chemotherapy regimens and either intrathecal methotrexate sodium during induction and consolidation plus 18 Gy of cranial irradiation or intrathecal methotrexate during induction, consolidation, and maintenance as central nervous system prophylaxis. The groups were comparable with regard to chronologic age, sex, and family socioeconomic status. Children who received cranial irradiation plus intrathecal methotrexate scored significantly lower on the McCarthy Motor Scale (P < .05) and the Token Test (P < .05) than children who received intrathecal methotrexate alone. The groups did not differ significantly on the McCarthy General Cognitive Index, Developmental Test of Visual Motor Integration, or Peabody Picture Vocabulary Test-Revised. Findings suggest that the combined effects of cranial irradiation and intrathecal methotrexate therapy on neuropsychological performance may be evident in young children as early as 9 months after diagnosis. Follow-up assessment of these children will reveal whether these effects remain constant, intensify, or resolve.

The "88% Saturation Test": A Simple Lung Function Test for Young Children

The 88% saturation test (88%-SAT) was developed as an alternative to standard spirometry for those young children unable to perform standard forced expiratory maneuvers. In adults, this test revealed rapid desaturation in those persons with a history of asthma when compared with healthy control subjects. Similar findings in children were tested. Tertiary care hospital. Thirty-three former premature infants (28.3 +/- 2.3 weeks gestation), aged 5 to 7 years, who were participating in a follow-up study, were enrolled in this study. The study compared the 88%-SAT with standard spirometry and respiratory health characteristics ascertained through a parental questionnaire. The 88%-SAT consists of continuous measurement of hemoglobin saturation by pulse oximetry (SaO2) while the subject breathes a nonhumidified 12% oxygen and nitrogen mixture for 10 minutes or until SaO2 decreases to 88%, whichever occurs first. Abnormal 88%-SAT was defined as a decrease of SaO2 to 88% within the 10-minute period, and abnormal spirometry was defined using standardized values. Of the 20 children who successfully completed both spirometry and the 88%-SAT, 10 had normal spirometry results and did not desaturate to 88%, and 5 had abnormal spirometry and 88%-SAT results. Four children did not desaturate during the 88%-SAT, but had abnormal spirometry results, and one child had abnormal 88%-SAT results, but normal spirometry. Ten additional children completed the 88%-SAT, but not standard spirometry. Three children were unable to complete either test. Of those 30 children tested, 7 (23%) had a history of reactive airways disease, and all 7 had abnormal 88%-SAT results. The 88%-SAT had greater sensitivity (100% vs 75%) and specificity (87% vs 63%) than spirometry in identifying children with known reactive airways disease. The mean McCarthy general cognitive index (GCI) of the group performing both spirometry and the 88%-SAT (n = 20) achieved a mean (+/- SD) GCI of 96.2 +/- 16.7, and the group (n = 30) that completed the 88%-SAT had a mean (+/- SD) GCI of 75.2 +/- 26.3 (chi 2 P < .012). The 10 children able to perform only the 88%-SAT had a mean GCI (+/- SD) of 72.8 +/- 26.9, and the 3 children unable to perform either test had a mean GCI (+/- SD) of 63 +/- 11. Our data suggest that the 88%-SAT may be more effective than spirometry for identifying reactive airways disease in young, uncooperative, or developmentally delayed children. The dry air of the hypoxic inspired gas may function as an airway challenge, leading to decreased oxygenation in patients with reactive airways.

Concurrent Validity of the WPPSI—R and the McCarthy Scales of Children's Abilities

The concurrent validity of the Wechsler Preschool and Primary Scale of Intelligence—Revised (WPPSI—R) and the McCarthy Scales of Children's Abilities was assessed with 32 preschool and kindergarten children. The correlations of .70, .73, and .81 between the McCarthy General Cognitive Index and WPPSI—R IQs on the Verbal, Performance, and Full Scales were significantly different from zero. There were no differences among the three WPPSI—R means and the McCarthy General Cognitive Index mean for the total group, or for gender means.

Impact of a Matched Term Control Group on Interpretation of Developmental Performance in Preterm Infants

One hundred twenty-four children who were born at 24 to 31 weeks' gestation and 124 term children matched in social background underwent serial developmental evaluations. The Bayley Mental Developmental Index at 6, 15, and 24 months and the McCarthy General Cognitive Index at 4 years were used to classify cognitive outcome for preterm children as normal (indices higher than 1 SD below the mean), mild-moderately delayed (indices between 1 and 2 SD below the mean), or severely delayed (indices > or = 2 SD below the mean). Classifications based on norms derived from the performance of the term control group were compared with those based on published standardized test scores. The control group had substantially higher mean (+/- SD) Bayley Mental Developmental Indices at 6 (111 +/- 11), 15 (114 +/- 13), and 24 months (115 +/- 21) than the published test mean (100 +/- 16). Consequently, significantly more preterm children were classified as normal when the Bayley test mean was used than when the performance of the control group was used to define the normal range (84% vs 52% at 6 months, 82% vs 49% at 15 months, and 70% vs 47% at 24 months). Severe cognitive delays were infrequent when defined by test mean (6% to 11%) but two to three times greater when the control group scores were used. In contrast, the control group had a mean McCarthy General Cognitive Index at 4 years (102 +/- 14) that was similar to the published test mean (100 +/- 16).(ABSTRACT TRUNCATED AT 250 WORDS)

Predicting preschool motor and cognitive performance in appropriate‐for‐gestational‐age children born at ≤ 32 weeks gestation

AbstractAlthough many follow‐up studies have been performed on preterm infants, little attention has been devoted to prediction of motor skills in the preschool or school years. We studied the relationship of performance on the Bayley Scales of Infant Development at a mean corrected age of 21 months to performance on the McCarthy Scales of Children's Abilities at a mean corrected age of 44.7 months for 43 appropriate‐for‐gestational‐age (AGA) children born at ≤ 32 weeks gestation. Motor scores were stable over time with a significant correlation between the Bayley Psychomotor Developmental Index (PDI) and the McCarthy Motor subscale (r = 0.60; p = 0.0001). Scores of cognitive abilities also showed a significant correlation between the Bayley Mental Developmental Index (MDI) and the McCarthy General Cognitive Index (r = 0.42; p = 0.009). Small‐for‐gestational‐age (SGA), very low‐birthweight (≤ 1500 grams) children scored lower on the McCarthy General Cognitive Index (p = 0.01) and on the Motor subscale (p = 0.047) than the AGA children. We concluded that motor performance of AGA children born at ≤ 32 weeks gestation is stable from toddlerhood to preschool age. We suggest that SGA children be excluded from studies of motor performance of prematurely born children.

Acute neonatal morbidity and long-term central nervous system sequelae of perinatal asphyxia in term infants

Twenty-eight term neonates with severe perinatal asphyxia were referred to a tertiary neonatal intensive care unit (NICU). The morbidity of asphyxia included involvement of the pulmonary ( n = 24 infants), central nervous system ( n = 22), renal ( n = 15), cardiac ( n = 14), metabolic ( n = 13) and hematologic ( n = 10) systems. The majority of neonates had more than three organ systems involved. Twenty-four neonates survived the neonatal course and at NICU discharge all system effects other than the central nervous system had resolved. At 5 years (60 months), 14 children had a normal neurologic examination, 9 had spastic quadriplegia and one had hemiplegia. Nine children had a McCarthy General Cognitive Index (GCI) ≥ 84, 3 had a GCI between 68 and 83 and 12 scored < 67. Neonatal seizures, renal problems, microcephaly at 3 months, and post-neonatal seizures were associated with an abnormal neurologic outcome or a GCI < 67. A neurologic examination during the first year of life may reveal whether children with birth asphyxia will be relatively normal at age 5 years or whether they will show considerable delay.

Individual Differences in Language Delayed Children's Responses to Direct and Interactive Preschool Instruction

This study examined the relative effects of two highly contrasting preschool curricula on language development for children with delayed language. Direct Instruction (DI) and Mediated Learning (ML) were compared in a randomized design. Systematic observations documented implementation of the programs and differences between the programs. No main effect differences were found between programs. Aptitude by treatment interaction analyses indicated that children with relatively higher scores on the pretest McCarthy General Cognitive Index and pretest Preschool Language Assessment Inventory benefited to a greater degree in language development from Direct Instruction, whereas relatively lower performing students on the two pretest variables gained more language skills from the Mediated Learning curriculum.

K-ABC and McCarthy scale performance among “at-risk” and normal preschoolers

This study assessed the degree of comparability between the McCarthy Scales of Children's Abilities (McCarthy) and the Kaufman Assessment Battery for Children (K-ABC) for 51 “at-risk” (Low Birthweight, Head Start, and Developmentally Delayed) and 33 “normal” preschool children. The K-ABC Mental Processing Composite (MPC) and McCarthy General Cognitive Index (GCI) correlated significantly for both groups, but was significantly greater for the at-risk preschoolers. The at-risk group achieved a significantly higher mean MPC than GCI, while the normal comparison subjects achieved a slightly lower mean MPC. As reflected in previous studies, the GCI seems to provide an accurate estimate of the at-risk child's typical classroom performance. While the MPC may afford an estimate of such children's capacity for academic growth, if provided appropriately tailored remediation, it may also be missing critical aspects of children's cognitive functioning. Mean score discrepancies for at-risk preschoolers were discussed in relation to the theoretical and psychometric properties of the K-ABC and McCarthy.