Significant subtest score differences on the WISC-R

Psychologists must often make decisions about the significance of scaled score differences between subtests on the WISC-R. Differences which statistically significant at the .05 and .01 level are presented. Generally, minimum differences of 3 to 5 points are necessary at the .05 level and 4 to 6 points at the .01 level. Cautions concerning the interpretation of statistically significant differences are discussed.     

Gender differences on the WPPSI, the WISC-R, and the WPPSI-R

The WPPSI, WISC-R, and WPPSI-R were administered in a counterbalanced design to 72 children between the ages of 5 years, 10 months, 16 days, and 6 years, 7 months, and 15 days to test the hypothesis that mean verbal IQs on these scales would be higher for boys than for girls. Results indicated that the mean verbal IQs for boys were significantly (p<.05) higher than those for girls on all three scales. Also, significant (p<.05) differences favoring boys were found onVocabulary andComprehension subtests on all three scales. These differences are probably a peculiarity of these scales and may not need any elaborate theoretical explanation. However, clinical uses of verbal and performance IQ discrepancies may not justifiably ignore the examinees’ gender.     

Gender differences on the WPPSI,the WISC-R,and the WPPSI-R

The WPPSI, WISC-R, and WPPSI-R were administered in a counterbalanced design to 72 children between the ages of 5 years, 10 months, 16 days, and 6 years, 7 months, and 15 days to test the hypothesis that mean verbal IQs on these scales would be higher for boys than for girls. Results indicated that the mean verbal IQs for boys were significantly (p<.05) higher than those for girls on all three scales. Also, significant (p<.05) differences favoring boys were found onVocabulary andComprehension subtests on all three scales. These differences are probably a peculiarity of these scales and may not need any elaborate theoretical explanation. However, clinical uses of verbal and performance IQ discrepancies may not justifiably ignore the examinees’ gender.     

The effects of positive examiner verbal comments on the total WISC-R performance of institutionalized EMR students

Forty educably mentally retarded (EMR) students were randomly selected and assigned to one of two treatment groups. Students in the experimental group were verbally praised after their responses to the WISC-R questions, while the students in the control group received nonevaluative procedural comments. The scaled scores for five of eleven subtests, in addition to the Verbal, Performance and Full Scale indices, were significantly greater under the experimental procedure. The treatment's efficacy and considerations for future research were noted and discussed.     

Comparison of black-white differences on the WISC-R and the K-ABC: Spearman's hypothesis

The Kaufman Assessment Battery for Children (K-ABC) and the Wechsler Intelligence Scale for Children-Revise (WISC-R) are compared with respect to the magnitudes of the average white-black differences in standardized scaled scores and in raw scores. The two test batteries were administered to a sample of 172 fourth- and fifth-grade children comprising 86 black-white pairs matched on age, sex, school, and socioeconomic status. The K-ABC and WISC-R are highly correlated, and the general factor, or g, of one battery is virtually identical to the g of the other. The high positive correlation between the size of the white-black difference on the various subtests of both batteries and the subtests' loadings on the g factor bears out Spearman's hypothesis that a test's white-black dicriminability is a direct function of the test's g loading. The lesser white-black discriminability of the K-ABC relative to the WISC-R is attributable to (1) the smaller g loadings of the K-ABC subsets and (2) the presence of other factors, particularly sequential short-term memory which, to some degree, offsets the white-black difference in g.     

Trade-off between memory for verbal items and their visual attributes.

Instructions to attend to the case and color in which words were presented led to improved retention of these visual attributes but depressed recognition performance. This trade-off between item and attribute memory occurred at three presentation rates (1.5, 5.5, and 10.5 sec/item), suggesting that visual attributes of verbal stimuli are rarely stored unless subjects expect that knowledge of physical form will be useful later. Visual attributes of high-imagery words were retained better than visual attributes of low imagery words by subjects instructed to attend to case and color, but not by subjects asked only to attend to word meaning. Implications of these findings for the hypothesis that visually presented verbal stimuli are stored as literal copies are discussed.     

Sex differences in early verbal and non‐verbal cognitive development

The present study of over 3000 2‐year‐old twin pairs used a sex‐limitation model to examine genetic and environmental origins of sex differences in verbal and non‐verbal cognitive ability. Girls scored significantly higher on both measures (p<0.0001), although gender only accounted for approximately 3% of the variance in verbal ability and 1% of the variance in non‐verbal cognitive ability. For the verbal measure boys showed greater heritability than girls. Also the twin‐pair correlation is significantly lower for opposite‐sex twins than for non‐identical same‐sex twins. This indicates that individual differences in verbal ability include some sex‐specific factors. Non‐verbal cognitive ability did not differ in aetiology for boys and girls. We conclude that genetic and environmental influences differ for girls and boys for early verbal but not non‐verbal development.     

Cultural influences on responses to items on the strong interest inventory

This study examined racial/ethnic group differences on an interest inventory at the item level using differential bundle functioning (DBF) analyses. Specifically, responses of males and females from five different racial/ethnic groups (N=3750) on the General Occupational Themes of the Strong were examined. Items were grouped together based on substantive considerations to determine if they functioned differentially due to racial/ethnic group differences in role modeling, perceptions of opportunities/barriers, familiarity with activities, and cultural expectations, as opposed to true racial/ethnic group differences in interests. Very high levels of DBF were found for most of the item sets considered in this study, implying that diverse cultural groups have a different conditional probability of endorsing some sets of items due to the items measuring a secondary trait in addition to the main trait the scale was designed to measure.     

Age-related differences in the specificity of verbal encoding

A communication paradigm was used as an analogue to cued recall to separate age-related differences in encoding and retrieval. Younger and older adults (senders) generated a series of one-word clues that would enable other subjects (receivers) to generate a designated target word. Clue and target generation tasks, analogous to the encoding and retrieval components of cued recall, were conducted in the context of either a strong or a weak associate of the target. Clues generated by older senders were less effective than clues generated by younger senders in enabling receivers to generate targets, especially when clues or targets were generated in the context of a weak associate. A deficit among older receivers was also obtained, especially when a weak-rather than a strong-associate context word was given to the receiver. Older adults experience difficulty with encoding and retrieval tasks that require processing of context-specific information that is not part of the generic information typically associated with a stimulus.