Journal qf' Personalitj~Assessment. 1978, 42, 3

The Utility of Two Wechsler Adult Intelligence Scale Short Forms with Prisoners W. M. NELSON. 111 University of Texas Health Science Center a t Dallas

JACK D. EDINGER Butner Federal Correctional Institution and

J O H N WALLACE Petersburg Federal Correctional Institution

Sumrnar,~:Previous research has suggested that the Pauker (1963) and Sat! and Mogul (1962) short forms of the WAIS have beenefficaciousinestimating thestandard form. While there is a growing need in correctional settings for quicker evaluation pr0cedure.r. thelack of WAIS short form research with prisoners prohibits their use with such populations. Hence. this study employed 126youngaduit maleinmates to test thecomparabilityoftheabovec~tcd short forms and the standard WAIS across a variety of evaluative criteria. The resuItsgene1-ally suggested the superiority of the Pauker (1963) form in estimating the standard WAIS. However. becausethecurrent study employed only blackand white young male offenders it i k suggested that the current findings not be generalized t o other age groups, races, or women inmates until these findings are cross-validated on such samples.

With the growing demands for psychological services, mental health professionals in a variety of settings are increasingly becoming aware of the need for incrementing their efficiency in direct services. This state of affairs is particularly true in most correctional institutions since such settings often have relatively few psychologists to serve their large inmate populations. At the time of conceptualizing this study, for example, the Petersburg Federal Correctional Institution's psychology service staff consisted of two full-time clinical psychologists, one full-time clinical psychologist trainee, one part-time (10 hours/ week) clinical psychologist consultant, and one part-time (10 hoursiweek) practicum student to serve the evaluation/treatment needs of over700inmates. Further, through the authors'contacts with other federal and state institutions it appeared that demands for correctional psychologists' time were increasing in various prison facilities. Consequently, incrementing efficiency in the provision of direct evaluative a n d / o r treatment services to individual inmates seemed of The views expressed in this manuscr~ptare exclusively those of the authors and do not necessarily reflect the views held by the United States Bureau of Prison\.

paramount importance. One means of increasing direct service efficiency is the shortening of the psychological evaluation process (Finch, Thornton, & Montgomery, 1974). T o reduce evaluation time various authors have suggested the use of shortened forms of individually administered tests such as the Wechsler Adult Intelligence Scale (WAIS). While various selected subtest (Doppelt, 1956; Karras, 1963; Maxwell, 1957) and selected item (Pauker, 1963: Satz & Mogel, 1962) abbreviated W A l S forms have been proposed, research(Edinger & Norwood, 1975; Finch, Thornton, & Montgomery, 1974) supports the efficacy of only the selected item forms. No studies, however. have attempted to investigate the utility of these selected item forms with prison populations and, hence, it is questionable whether either of the selected item forms are efficacious for inmate groups. Consequently. the purpose of this study was to investigate the comparability of the above cited selected item short forms and the standard WAIS within a n inmate population. T o evaluate these short forms severai criteria were employed. First, the thret criteria proposed by Resnick and Entir, (1971) were adopted so as to determint. the comparability of theabbreviated anc:

W. M . NELSON, 111, J. D. EDINGER, and J . WALLACE standard form 1Q scores. For a short form t o be considered comparable to the standard WAIS these criteria state that: (a) correlations between short and standard form IQ scores should be significant, (b) t tests between the mean short and standard form 1Q scores should be nonsignificant, and (c) the percentage of IQ diagnostic classification change should not be so great as to preclude t he effective use of the short form. In addition to these criteria, it was decided to investigate the comparability of these two short forms and the standard WAIS in terms of subtest profile configurations. Since subtest "profileanalysis" (Zimmerman & Woo-Sam, 1973) is often employed in clinical prediction it seemed that short and standard WAIS profiles should be comparable. Further, since various authors (Holmes, Armstrong, Johnson, & Ries, 1966; Merkle, 1968; Watkins & Kinsie, 1970) have questioned the comparability of short and standard form profiles it seemed essential to evaluate their comparability. Hence, the authors adopted the criterion rule that the correlation between a subject's short and standard form subtest scores should be significant and of such a magnitude as to allow comparable clinical predictions from short and standard form subtest scores. A further concern of the authors was whether the short and standard forms are similar in terms of their factor structures. Seemingly if aspecific WAIS short form is an accurateapproximation of the standard WAIS, then clusters of intellective abilities measured by short and standard forms should be similar. Therefore, it seemed of theoretical importance to evaluate the comparability of short and standard form factor structures. Thus, the authorsadopted theevaluative criterion rule that the number of factors and the subtest loadings on these factors should be similar for short and standard WAIS forms so that these forms may be comparable in reference t o the manner in which they measure intelligence. A final area concerning the authors was that of thecomparability oftheshort and standard forms in the prediction of external criteria. Specifically, it seemed

303

that if a particular short form isa reliable estimate of the standard W A l S then that form should predict external criteria a t a level equal to that of the standard WAIS. Consequently, the comparability of the short and standard WAIS forms in predicting external criteria was selected as a final means of evaluating the two short forms. With these various evaluative criteria delineated, the authors effected the following study to determine the relative efficacy of the Satz and Mogel(1962) and Pauker (1963) WAIS short forms with an inmate population. Method Subjects The subjects selected for this study were 126 male inmates of the Petersburg Federal Correctional Institution. These 126 subjects represented all inmates who had been administered the entire WAIS and who had this test data as well as Beta I Q and Stanford Achievement Test (SAT) Scores available in the institution's psychology service's files. Sixty-three of these subjects were Black and 63 were White. The mean age of the Blacks was 2 1.17 years (Range = 17 to 26 years); the mean age of the Whites was 22.14 years (Range = 18 to 26 years). The mean Verbal, Performance and Full Scale 1Qs of the Blacks were 92.95, 94.27, and 93.1 1 respectively. The mean Verbal Performance and Full Scale 1Qs of the Whites respectivzly were 103.89, 104.79, and 104.54. Of the 126 subjects 55 (43.65%) had been incarcerated on charges of robbery, rape, murder, or other crimes against persons, 32 (25.39%) for burglary, larceny, theft, or other property crimes, 24(19.04%) for drug-related offenses, and the remaining I5 (1 1.98%) for other miscellaneous offenses. Procedure T o obtain a sample of subjects, the psychology files of FCI, Petersburg were reviewed and all filescontaininga WAIS protocol, SAT scores and Beta IQ scores, all of which had been obtained upon the inmate's admission t o the prison, were selected. Following this procedure files not containing WAlS subtest scores for all 1 1 subtests were eliminated. With these

304

Use of Two WAIS Short Forms with Prisoners

omissions 126 files remained, 63 of which were Black inmates' files and 63 of which were the files of White inmates. Subsequent to this selection process the 11 subtest scaled scores, Verbal IQ, Performance IQ, Full-scale IQ, Beta IQ, and SAT scores were obtained for each subject. Also each WAIS protocol was scored separately using both Pauker's (1963) and Satz and Mogel's (1962) selected items. From these scorings estimates of each subtest scaled score as well as Verbal, Performance and Full-scale IQ scores for each of the two short forms were obtained. Subsequently, a series of statistics, computed within each racial group separately, were used to evaluate the short forms in terms of the above described criteria. Specifically, these statistics involved the following four series of comparisons: 1. Resnick and Entin (1971) Criteria: Included among these comparisons were the calculation of Pearson Product-Moment correlations between short and standard form IQs, the calculation o f t values between short and standard form IQ means, and the determination of the percentage of each sample which was diagnostically misclassified by each short form full-scale IQ. 2. Profile Comparisons: Included in these comparisons were the calculation of Pearson Product-Moment correlations between short and standard forms' subtest scaled scores for each subject as well as the determination of the percentage of subjects from each racial group having nonsignificant short-standard form subtest correlations for each of the two short forms. 3. Comparisons of Factor Structures: Included in this evaluation were the determination of the comparability of the number of factors produced in factor analyzing the short and standard forms as well as the comparability of the subtest loadings on respective factors. 4. Prediction of External Criteria: These analyses were effected to determine the comparability of Pearson ProductMoment correlations produced in correlating short and standard forms with Beta IQ and Standard Achievement Test scores.

Results Resnick and Entin (1971) Criteria The results of both the Pearson correlations between short and standard form IQs as well as the t tests between short and standard form means are displayed in Table 1. As shown, thecorrelations within each racial group were very respectable ( p < .001) and only minor nonsignificant differences were obtained between the Pauker (1963) and Satz and Mogel (1962) forms in terms of these comparisons. Further, practically no differences in the magnitude of thesecorrelations were obtained for the Black and White subjects. In contrast the results oftheztestssuggested the superiority of the Pauker (1963) over the Satz and Mogel(1962) form in estimating the standard WAIS. Within the Black sample the Satz and Mogel verbal, performance and full-scale IQs all were significantly different from the standard WAIS scores. The Pauker (1963) form, however, produced Verbal, Performance and Full-scale IQs which were not significantly different from the respective standard form scores. While only the t test between the Satzand Mogel (1962) and standard form full-scale IQ means reached significance within the White group, a comparison of the mean IQ differences listed in Table 1 shows that the Pauker (1963) form provided a closer estimate of standard form IQs than did the Satz and Mogel(1962) form. Thus, the Pauker (1963) form seemed the better of the two in estimating standard form IQs. In terms of the number of subjects diagnostically misclassified the favorability of one form over the other varied across the races. For the Blacks the Pauker (1963) form was superior by virtue of its misclassifying only 6 (9.5%) of the 63 subjects as opposed to the 14 (22.2%) misclassified by the Satz and Mogel (1962) form. In contrast the Satz and Mogel(1962) form was slightly superior for the Whites in that it misclassified 11 (17.5%) of the 63 Whites as opposed to the 12 (19.0%)misclassified by the Pauker (1963) form. Hence, it appears that the achievement of the fewest diagnostic misclassifica-

305

W. M. NELSON, 111, J. D. EDINGER, and J. WALLACE Table 1

Abbreviated Form Means and Standard Deviations and Mean Differences, Correlations, and t Values Between the Standard WAIS and the Abbreviated Forms

MEAN

Standard Deviation

Mean Difference Standardibbreviated Form MEANS

r with Standard Form

t with Standard Form

Blacks Pauker Verbal IQ

1.36

Pauker Performance 1Q

0.70

Pauker Full Scale IQ

1.56

Satz & Mogel Verbal IQ

2.45**

Satz & Mogel Performance IQ Satz & Mogel Full Scale IQ

4.00*** 4.47"""

Whites Pauker Verbal IQ Pauker Performance IQ Pauker Full Scale IQ Satz & Mogel Verbal IQ Satz & Mogel Performance IQ Satz & Mogel Full Scale IQ

tions was achieved by different short forms with the two samples.

Profile Comparisons The correlational comparisons between standard and short form scaled scores resulted in slightly, albeit nonsignificantly ( p > .05), higher correlations for the Pauker (1963) than for the Satz and Mogel(1962) form across both

racial groups. F o r the Blacks the mean Pauker-standard form scaled score correlation was .78 (Range= .24 to .99); the mean Satz and Mogel-standard form correlation was .76 (Range = .36 to .97). Among the White subjects the mean Pauker-standard form scale score correlation was .82 (Range = .28 to 1.00); the mean Satz and Mogel-Standard form correlation was .80(Range=-.02 to 1.00).

Use of TK*OWA /S Shorf Forms w'irh Prisoners

W. M. NELSON, Ill, J. D. EDINGER, and J. WALLACE Table 3 Pearson Product-Moment Correlations Between the Standard Form and the Abbreviated Form Factors -

-

Pauker Factors

1

Satz & Mogel

Blacks Standard Form I I1 -

-

Whites Standard Form I I1 111

Coupled with these findings, it was discovered that each sample had a greater percentage of nonsignificant Satz and Mogel-standard form scaled score correlations than they had of Pauker-standard form correlations. Specifically, 19% of the blacks and 11.1% of the whites had nonsignificant Satz and Mogel-standard scaled score correlations. These figures were slightly higher than the l2.7%of the blacks and the 7.8% of the whites having nonsignificant Pauker-standard form scaled score correlations. Consequently, the Pauker (1963) form seemed slightly superior to the Satz and Mogel (1962) form in approximating the standard form's profile configurations. Comparisons of Factor Structures Principal components factor analyses with Kaiser's (1958) varimax solution were applied to short and standard forms subtest scaled scores. The results of these analyses are reported in Table 2. As shown, the Pauker (1963) form was more similar to the standard WAIS than was the Satz and Mogel (1962) form in terms of the

number of factors produced. In fact, for both the Black and White samples the factor analysis of the Satz and Mogel form resulted in one more significant (i.e., having an Eigen 1 1.00)factor than did the factoring ofthe standard WAIS. In contrast, the factor analysis of the Pauker (1963) form resulted in the exact number of factors produced by factoring the standard form. To determine the comparability of respective factors the factor loadings of standard and both abbreviated forms were intercorrelated using Pearson's r. These correlations are reported in Table 3. The correlations between the respective factors of the Pauker (1963) and standard forms generally were positive and high with the single exception of the factor I1 correlation among the Whites. The correlation between respective factors of the Satz and Mogel and standard WAIS also were generally positive but of a lesser magnitude than those between the Pauker and standard forms. In fact, for the White inmates none of the Satz and Mogelstandard form respective factor correla-

308

Use o f TM.OWA IS Short Forms with hisoners Table 4 Pearson Product-Moment Correlations of Standard and Abbreviated Form Verbal, Performance and Full Scale IQ with Beta IQ and SAT Scores Blacks Stanford Achievement

Whites Beta 1Q

Stanford 4chievement

Standard Form Verbal 1Q

.49

33

Standard Form Performance IQ

.75

.7i

Standard Form Full-Scale IQ

.67

.81

Pauker Verbal IQ

.48

.84

Pauker Performance IQ

.58

Pauker Full-scale IQ

.66 .62

Satz & Mogel Verbal IQ

.46

.82

Satz & Mogel Performance IQ

.70

.54

Satz & Mogel Full-Scale IQ

.65

.8 1

Beta IQ

32

Note: ALL correlations are significant at the p < .001 level. tions were significant. Further, the only correlations were slightly more similar correlational comparison showing a to the standard form-Beta IQ correlagreater positive relationship between re- tions than were those between the Pauker spective factors of the standard and Satz form and Beta IQs. In predicting S A T scores again the and Mogel (1962) form than between respective factors of the Pauker (1963) comparability of the short and standard and standard forms was that for factor I1 forms varied across the two races. For within the White sample. Thus, for these the Blacks the Satz and Mogel-Stanford samples the Pauker (1963) form seemed Achievement Test correlations were the closer approximation to the standard slightly closer to the standard WAISform both in terms of the number of fac- Stanford Achievement Test correlations tors produced and in terms of the struc- than were the Pauker-Stanford Achievement Test correlations. Among the of respective factors. Whites the reverse of these findings was Prediction of External Criteria true. These results suggest that the comTable 4 displays the Pearson Product- parability of the short and standard Moment correlations computed between forms in terms of predicting these exter: each of the three WAIS forms 1Qs and nal criteria varies both in terms of thecrithe external criteria of Beta I Q and Stan- terion predicted and in terms of the race ford Achievement Test scores. For the of the subject in question. However. it Black subjects the Pauker-Beta IQ score should be noted that the above cited difcorrelations generally resembled the ferences between the two short forms standard form-Beta IQ score correlations were only slight and that both forms' more so than did those between the Satz correlations with the external criteria and Mogel and Beta IQ scores. The re- were reasonably close to those between verse of this was true for the whites. For these criteria and the standard form. Thus, this group the Beta IQ-Satz and Mogel these findings d o not conclusively favor

W. M. NELSON, 111, J. D. EDINGER, and J. WALLACE use of one form over the other with this population.

Discussion The present study was effected to investigate the utility of two WAIS short forms with a n inmate population. Specifically this study attempted t o determine how comparable the Satz and Mogel (1962) and the Pauker (1963) forms are to the standard WAIS across a number of evaluative criteria. The findings of this study are presented in summary form in Table 5. Although a few of the comparisons slightly favored the Satz and Mogel(1962) form, the majority of the comparisons suggested the superiority of the Pauker (1963) form with this population. Considering the Resnick and Entin (1971) criteria, for example, the Pauker form seemed generally superior to the Satz and Mogel(1962) form. In fact, for the Blacks, the Pauker (1963) form was as good as or better than the Satz and Mogel (1962) form in terms of all three criteria. Similarly, for the Whites the Pauker (1963) form was favored by virtue of its equaling or bettering the Satz and Mogel (1962) form o n five out of seven comparisons employed in effecting the Resnick and Entin (1971) criteria. Further, even those two comparisons favoring the Satz and Mogel(1962) form involved such slight differences between this and the Pauker (1963) form that these differences were statistically unreliable. Thus, based on these criteria, it seems that the Pauker (1963) form is the more efficacious with both Black and White inmates. Similar t o these findings, the results of both the profile and factor analytic comparisons favored the Pauker (1963) form. While both forms correlated at respectable levels with the standard form in terms of profile configurations, the Pauker (1963) form estimated the standard form at a slightly higher level for both races. Further, within both racial groups, the factor structure comparisons revealed the Pauker (1963) form to be the more efficacious in estimating both the number of standard form factors and the subtest loadings on these factors. Hence, these

309

findings suggest that, for this population, the Pauker (1963) form allows for clinical profile interpretations and measures intellective abilities in manners more similar to thestandard WAIS than does the Satz and Mogel(1962) form. In regard to the prediction of external criteria it appears that the comparability of the short forms and standard WAIS vary both as a function of the criterion predicted and as a function of the prisoner's race. For the Blacks, the prediction of Beta I Q scores seemed slightly better achieved by using the Pauker (1963) form while the prediction of SAT scores was better accomplished by using the Satz and Mogel(1962) form. In contrast, for the Whites the prediction of Beta IQs was better achieved using the Satzand Mogel (1962) form while the prediction of S A T scores was better accomplished by using the Pauker (1963) form. In summarizing these findings it seems the Pauker (1963) form seemed more comparable to the standard WAIS than did the Satz and Mogel(1962) form. As shown by Table 5 thePauker(l963)form equaled or bettered the Satz and Mogel (1962) form in estimating the standard form on 16 out of 18 evaluative comparisons employed with the Black subjects. Similarly, for the Whites the Pauker (1963) form was equal or superior to the Satz and Mogel(1962) form o n 14 out of 19 comparisons. Further, for both races, all comparisons favoring the Satz and Mogel(1962) over the Pauker (1963) entailed only slight, nonsignificant differences between these two forms. In contrast, many of the comparisons which favored the Pauker (1963) form suggested marked differences between this form and the Satz and Mogel(1962) form in approximating the standard WAIS. Hence, the correctional clinician, desirous of employing a WAIS short form with a comparable population, apparently should choose the Pauker (1963) over the Satz and Mogel(1962) form so as to achieve results which, across various criteria, are comparable to the standard WAIS. A word of caution regarding the generalizability of these findings, however, seems warranted. As discussed in the

310

Use of

Tw.0WAIS Shorr Forms ~ i r hPrisoners

Table 5 Comparison of the Two Abbreviated Forms Across the Multiple Criteria Employed Whites

Blacks --

Criterion

Short Form-Standard Form Correlations Verbal IQ Performance IQ Full-scale 1Q

Pauker

Satz & Mogel

Tie Tie

Tie Tie

Pauker

Satz & Mogel

Tie

Tie

t

t

t

Difference Between Short and Standard Form Means Verbal IQ Performance IQ Full-scale 1Q

t

+

t

t

+

+

% of Diagnostic Misclassifications

t

Profile Comparisons Subtest Correlations 5% Nonsignificant Correlations

t

t

t

t

t

+

+

t

Factor Structure Number of Factors Correlation Between Respective Factors I 11 111 Correlations with Beta IQ Verbal 1Q-Beta IQ Performance IQ-Beta 1Q Full-Scale IQ-Beta IQ Correlations with Stanford Achievement Test (SAT) Verbal IQ-SAT Performance IQ-SAT Full-scale IQ-SAT

t

t

t

N/A

N/A

Tie

Tie

t

+

+

+

t

t

Tie

Tie t

t

Tie

+ +

Tie

W. M. NELSON, 111, J. D. EDINGER,and J. WALLACE methods section, this study employed only Black and White young adult male inmates. Because of the specifics of this group, it is questionable whether these findings are generalizable to other age groups, other races, o r women prisoners. Thus, the correctional psychologist is warned against generalizing these findings t o other prisoner types until they are cross-validated on more varied prison samples. References Doppelt, J . E. Estimating the full scale score of the Wechsler Adult Intelligence Scale from scores on four subtests. JournalofConsulring P.~.vchology, 1956,20,63-66. Edinger, J . E., & Norwood, P. E. Relative efficacy of Wechsler Adult Intelligence Scaleshort forms with outpatients. Journal of Consulring and Clinical Ps.vchology, 1975.43. 59 1. Finch, A. J., Thornton, L. S., & Montgomery. L. E. WAIS short-forms with hospitalized psychiatric patients. Journal of Consulting and Clinical Psychology, 1974,42, 469. Holmes, D. S.. Armstrong. H. E., Jr., Johnson, M. H., & Ries, H. A. Validity andclinical utility of the Satz and Mogel abbreviated form of the WAIS. Pspchological Reporrs. 1966. 18. 992994. Kaiser. H. F. The varimaxcriterionforanalyticrotation in factor analysis. Psychomeirika. 1958. 23, 187-200.

31 1

Karras, A. Predicting full scale WAIS IQs from WAIS subtests for a psychiatric population. Journal of Clinical P s v c h o l o ~ , 1963. ~. 19, 100. Maxwell, E. Validities of abbreviated WAIS scales. Journal of Consulrina Pswholoar.. 1957. 21, Merkle, S. The effect on subtest differences of abbreviating the WAIS. Journal of Clinical Ps.1.cho1o.p. 1968,24. 196-197. Pauker. J. D. A split-halfabbreviationof the WAIS. Journal of Clinical P s , ~ c h o l o ~1963, ~ , 19.98- 100. Resnick, R. D., & Entin. A. D. Is an abbreviated form of the WISC' valid for Afro-American children? Journal of Consulting and Clinical Ps1,c h o l o g ~ 197 ~ . 1,36. 97-99. Satz. P.. & Mogel, S. Anabbreviation ofthe WAIS for clinical use. Journal of Clinical P:vchology. 1962, 18, 77-79. Watkins, J . F..& Kinsie, W. B. Exaggeratedscatter and less reliable profiles produced by the SatzMogel abbreviation of the WAIS. Journal of 1970, 26. 343-345. Clinical P.y~~cholo~ql., Zimmerman, I . L., & Woo-Sam. J. M. Clinicalinterpreration qf'the Wechsler Adult Intelligence Scale.. New York: Grune & Stratton, 1973.

Jack Edinger Mental Health Division Butner Federal Correctional Institution Butner. N.C. 27509 Received: July 14, 1977