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STUDY # 2: A COMPARISON OF MENTALLY HANDICAPPED CHILDREN WHOEXHIBIT HIGH OR LOW VARIABILITY OF THE SUBTESTS ON THE WECHSLERINTELLIGENCE SCALE FOR CHILDRENThe main purpose of this research is to determine ifProblem:mentally retarded children who differ in the amounts of variabilityon the Wechsler Intelligence Scale for Children also differ onother test measures, In a previous study, the author establisheda profile of abilities for the mentally retarded child as testedby the WISC. This research showed the retarded child to be higheston the non-verbal, concretes non-academic subtests of the WISC(Picture Completion and Object Assembly) and lowest on the verbalabstract and academic oriented subtests (Vocabulary and Arithmetic:,Upon examination of the data of this study, it was found thatsome subjects had a very even profile of scores on the WISC„while others had marked deviations. It was hypothesized that thesubjects whoce WISC profiles were even would differ from thesubjects with many deviations on measures of brain injury andachievement.Method: Agroup of 100 subjects from a previous study was used.Using the WISC protocol for each of thee subjects the variability,In the form of the standard deviation of subtest scores, wascomputed The moan standard deviation for this group was computedat 14.44 with a S.D. of 4.22. The subjects were then separatedinto three group's group one consisted of the subjects with highvariability (one standard deviation above the moan), group twoconsisted of those subjects with a low amount of variability (one

standard deviation below the mean), while group three consistedof the subjects with an average amount of variability (plus orminus one standard deviation from the mean), Group one consistedof 19 subjects as did group two, Group three (N 62) was not usedin this study.Medical records of the subjects of groups one and two werethoroughly checked for evidence of medical diagnosis of braininjury, No statistical tests were used to compare the incidenceof brain injury between these two groups. Only the total ofsuch incidences were tallied.Each of the subjects was also given the Wide Range AchievementTest (WRAT)0 Only 18 of the subjects of group one and 17 subjectsof group two were available for tasting, The mean standard scores(S,S.) of the Spelling, Arithmetic and Reading sections of theWRAT were treated as an Achievement Quotient (A.Q.) and compared withthe I.Q. score of each subject. A Pearson Product-MomentCorrelation Coefficient was found for each group with a z testrun between the correlation coefficients,Resups:Incidence of brain injury in case history:Group one (high variability)6Group two (low variability)1 casecasesCorrelation coefficient between achievement (A.Q.) andintelligenceGroup one2E22R.112No1817Mean I.Q.5901757041

Mean A.Q0aGIOUD oneGroup two65,24 04167,53 .77z is 10 58 (Not significant at ,05 level') a value of 1096 was needed for significance at the 005 levelDiscussion: As can be seen from the previous results, group one(high variability) had six inoidemes of brain injury out of 19subjects, while group two (low variability) had only one caseout of 19, Although this is not considered significant evidence,it is felt that it is at least irdicating a trend, That is, itappears that more brain injured children were contained in gropone than in group two,Also, from the above results, group two had a'highcrcorrelation between intelligence and achievement ( 077) than didgroup two( Al). Although the difference between these twocorrelation coefficients is not statistically significant, it isfelt that this difference points to an important educationaltrend, That is, group two appears to be achieving closer to theirability than group One,Summary;, The purpose of this Study is to determine if a groupof 19 subjects who showed little variability on the WI5C woulddiffer on other measures from a group of 19 subjects wit., highvariability. A cheek through the complete medical histories ofthe subjects revealed six caset of brain injury in group one(high variability), but only one case in group two (low variability),Furthermore, a correlation coefficient of 077 was found for

group two when intelligence and achievement wore compared.Group one showed a correlation of only ,41, thus indicatingthat group two was achieving closer to their ability than wasgroup one.A tentative hypothesis is that group one achieved at alower rate because of a higher occurance of brain injury.Furthermore, since group one had high variability between thesubtests of the OISC, a high medical incidence of brain injuryin their case histories and a low level of achievement whencompared with intelligence, it is, therefore, hypothesized thatgroup one consisted primarily of brain-injured retarded children(exogenous), Also, it is hypothesized that group two consistedprimarily of non brain injured (endogenous) mental defectives,However, further research is needed to substantiate thesehypotheses.

.STUDY # 31 THE USE OF THE WECHSLER INTELLIGENCE SCALE FORCHILDREN IN DIFFERENTIATING BETWEEN THE ENDOGENOUS AND EXOGENOUSMENTAL DEFECTIVEIntroduction: Proposed Dissertation StudyFor many years,special education programs for the educable mentelly retardedhave attempted to use similar teaching methods for all retardedchildren, These methods were aimed at helping the non-brain injuredretardates and adve.eated the use of a large variety of learningexperiences with ri high level of stimulation (Kirk, 1963, pp,120421; Frankel et al, 1966,pp. 9-11.)The main concern of theeducator has been to differentiate between the retarded and thenon retarded child with secondary concern given to the classificationof trainable and educable retardation, Little or no concern hasbeen devoted to further differentiation within the group ofE.H.R. children.Statement of theproblem:The problem to be investigated in thisresearch is to identify those measured skills contained withinthe Wechsler Intelligence Scale for Children (WISC) which willdifferentiate the endogenous type mental defective from theexogenous retardate,Rationale: Theneed for devising a method of differentialdiagnosis for the mentally retarded is to enable the educator tomore effectively group these exceptional children for the purposeof instruction, Historically, it has been assumed that E.H.R.children composed a homogenous group by virtue of having.

homogenous I.Q. scores. However, there has been some evidence(Martinson and Strauss„ 1940) that indicated that the erogenous(brain-injured) retardate requires a different educational programfrom the endogenous (nonebraineinjured) mental defecGive, intheir study, Eartinson am Strauss (1940) found the endogenous childto be very slow in learning new behaviors and new tasks, but veryable to work on the same task for long periods of time„ Theexogenous type children were found to be lacking in the skills ofattention, They were more disorganized, incoherent and distract able. than the endogenous child, Therefore, from paw; experience,it has been evident that there is a need for two types of programsfor the mentally retarded However, the current trend is for asingle grouping of educable mentally retarded children forpurposes of educational instruction.It is felt that the main reasons for homozonous grouping ofeducable mental retardatee have been the lack of adequate organizatlon to provide two separate programs for retarded childrenand the lack of adequate instruments and methods of differentiatingbetween the two groups of mental defectives. It is also feltthat the former is the easier to remediate.Since a medical diegnosis has been required in the pest formaking a discrimination between the endogenous and the exogenousmental detective, most educational institutions have found itdifficult to finance such a program of diagnostics, However,many school systems employ specialists, such as educational,school or clinical psychologists who are qualified to use alarge nrmber of test instruments and to make certain educationaland/or psychological diagnoses, Thepsychologistemployed in the

school should be capable of differentiuting between the endogenous and exogenous type mental defective, It is also feltthat with proper use, any number of test instruments would bevalid for use as described above0 However, because of the rangeof abilities tested and its widespread use and familiarity, theWechsler Intelligence Scale for Children (WISC) was chosen forthis study. The method of differential diagnosis is the remainingproblem to be investigated in this study0021114tiqn of termei1. Endogenous mental defectives A medical diagnosis hasshoWill (1) the presence of mental deficiency among the members ofthe immediate family, (2) the absence of significant factors inthe birth and developmental history, according to the case record,and (3) the absence of neurological signs of each of these subjects.2. Exogenous mental defective: Each subject in this classifiecation hats been medically diagnosed as having: (1) no evidence ofmental deficiency in the members of the immediate family, (2) ahistory of pre natal, natal or post-natal injury to the brain,either of a traumatic nature or due to an inflammatory process& or(3) the presence of neurological signs of brain lesion. Thesedefinitions are similar to those used by Frazeur and Hoakley (190)03. Strauss treatment method: According to Martinson and Strauss(1940), the exogenous child requires a treatment program whichUtilizes a variety of approaches, such that the most proper approachcan be used depending upon the pattern of damage resulting fromthe organic defect.4. Traditional treatment method: Martinson and Strauss (1940)

.also state that the endogenous child learns at a much slower ratethan does the normal child. Therefore, it is nocessary to trginthe child intensively, using carefully selected materials, butwith a very basic method, Since most programs view the retardedchild as if he were of the endogenous type and prepare his programas such, the method of teaching the endogenous child will beconsidered as the traditional treatment method.Limitationspf this study: This study is faced with the limitationscaused by the definitions of the endogenous and the exogenous typomental defective. By using a medical approech for differentiatingbetween the endogenous and the exogenous types of deficiency,certain inconsistencies of diggnosis will be present. ?or example,parental pressure could affect the final diagnosis, therebycausing an artificial increase in the number of brain-injured(exogenous) retardates. Furthermore, there exists considerablevariability of competency for such a diagnosis within the medicalprofession.Method:The 4ISC protocol of two hundred subjects were seleretedInto two groups, the endogenous and the exogenous mental defective *The results of each of the eleven subtests of the WI3C were usedfor each group. The scaled scores of each of the following eubteetswere used: Information, Comprehension, Arithmetic, Similarities,Vocabulary, Digit Span, Picture Completion, Picture Arrangement,Block Design, Object Assembly and Ceding Certain subtests scaledscores were combined totraits.yield composite scores measuring commonThe scaled scores of the followingsubtests were added

to yield a single score measuring a specific treit: Informationand Picture Completion (alertness); Comprehension and PictureArrangement (comprehension of social situations); Similaritiesand Block Design (concept formation); Information, Comprehension,Similarities and Vocabulary (verbal comprehension); Block Design,Object Assembly and Coding (visual-motor organization); andArithmetic, Digit Span and Coding (concentration).T-tests were run comparing the two groups on each of thesesix measures, Differences were considered significant at the .01level. The following hypotheses wore tested using these data:Hypothesis laThere are no differences between the endogenousand exogenous child as measured by the total of the verbal comprehension pubtests of the WISC. (Information, Comprehension, Similarities, and Vocabulary.)Hypothesis 2: There are no differences between the endogenousand the exogenous as measured by the total of the visual-motororganization cluster of the WISC (Block Design, Object Assembly,and Coding subtests).Hypothesis 3: There are no differences between the endogenousand the exoeenous as measured by the total of the Information andPicture Completion subtests of the WlSC (alertness cluster).Hypothesis k: There are no differences between the endogenousand the exogenous as measured by the total of the Comprehension andPicture Arrangement subtests of the WISC (comprehension of socialsituations.Hypothesis 5: There are no differences between the endogenousand the exogenous as measured by the total of the similarities andBlock Design eubtests of the WISC (concept formation).

15.Hypothesis 6:There are no differences between the endogenousand the exogenous as measured by the total of Arithmetic, DigitSpan and Coding subtests of the W1SC (Concentration).The verbal 1.4. and the performance I.e. of each subject wasused for the next part of the study. The difference between theVerbal I.Q. and the Performance IA. of each subject was computedby subtracting the Performance 1.40 from the Verbal I.Q. A t-testwas run comparing the two groups of subjects on this measure of thedifference between verbal and nonverbal abilities. Significanceagain was sought at the 001 level. The following hyuothesis wastested using these data.Hypothesis. 7: There are no differences between the endogenousand the exogenous as meesured by the difference between the Verbal10Q0 and the Performance 14Q0 of the WISC(VIQ PIQ)The variance of the scaled scores for the eleven subtcsts ofthe WISC were computed for each subject. The value of the variancewas used as an index of intratost variability, A tetest was runcomparing the two groups on this measure. A .01 level of significance was sought. The following hypothesis was tested using thesedata:Hypothesis 8: There are no differences between the endogenousand the exogenous as measured by an index of intrateet variabilityOf the 'WISC.Lastly, a measure of tntertest variability was computed foreach subject. Each time a subject completed a difficult problemor answered a difficult lima after he had previously failed aneasier one (scored as zero) one point was tabulated. This wasdone with all of the subtests except Digit Span and Coding. For18

theDigit Span subtest, an inconsistency was scored when thesubject passed an item on the second attempt after failing thefirst, No measure of inconsistency was attempted for the Codingsubtest, Ifaftera subject passed two or more items in successionfailing the easier item, a score of only one point wascounted.Only the inconsistenciesof failures were scored and summedfor the measure of intertest variability. A t-test was then runcomparing the endogenous and the exogenous groups. A .01 level ofsignificance was sought. The following hypothesis was tested usingthese data:Hypothesis 9: There are no differences between the endogenousand the exogenous as measured by an index of the total intertestvariability of the WISC.Expected Results: In summary of the previous studies dealing withendogenous and exogenous mental defectives, it appears that theendogenous.exogenous classifications can be differentiated accordingto the following: the endogenous child has been found to besuperior to the exogenous child on tasksrequiring concept formation,visual perception, visual—motor ability, memory and othernonverbalskills. The exogenous defective appears to be generally superiorto the endogenous child on verbal tasks. The exogenous child alsoappears to be more alert and more sociable. Furthermore, theexogenous child should show considerable more intertest and intra.test variability than does the endogenous child.Relating to the present study usingthe WISC, the literaturereview suggests that the endogenous child should be superior to theexogenous on those subtexts measuring concept formation (Similarities

plus Block Design) and visual motor organization (Block Design,Object Assembly and Coding). The exogenous child should prove tobe superior on those subtexts measuring verbal comprehension(Information, Comprehension, Similarities and Vocabulary); andalertness (Information, and Picture Completion) and comprehensionof social situations (Comprehension and Picture Arrangement).Furthermore, the difference between the Verbal I.Q. and thePerformance I.Q. should also indicate the verbal superiority ofthe exogenous group. Lastly, the exogenous group should alsoshow greater intertest and intratest variability than theendogenous group.

REFERENCESBaroff, G.S. WISC Patterning in Endogenous Mental Deficiency,ecarlaoftlentitlataancz,19590 64, 402-485.Wil.1.4Joij.EBeck, 11.S0 and Lam, ILL. Use of the WISC in Predicting Organicity Journakof ClInioalleyohologY, 1955, 13. 0 1541570Benaberg, G.J, A Test for Differentiating Endogenous and Exogenous.efacionsato 54Mental Defectives,aaiLvrisi2L2I22.LLenititik1950, 502.5060Bijou S.W The Psychometric Pattern Approach as an Aid to CnnicalMental Deficiency,46,Analysis - A Review. American Journal of1942, 354-3620Cassel, R.H. Relation of Design Reproduction to the Etiology ofMental Deficiency J urnal of Connultingjjal421262, 139 1949,Dolphin, J,E and Cruickshank, W,M. Pathology of Concept Formationin Children with Cerebral Palsy American Journal of Mental2111121.00a, 1952, 56 386.392,,Doll, E.A. Influence of Environment and Etiology on Social Competence, American Journal of MentiaLlifisiem, 19458 50, 89-.94Doll, EGA Practical Implications of the Endogenous.ExcgenousClassification of Mental Defectives American Journal of Mentalaugunt. 1946. 50, 503.511.therankel, M.0.0, Rapp, F.W. and Smith, Mao Functional Teaching ofte taRetarded Springfield, Illinois: 5;3177C0 Thomas.s er eFrazeur, H0A, and Roakley, Z,P. Significance of Psychological TestResults of Exogenous and Endogenous Children, American J2IlizaaplazeIll.Rulgaggi. 51, l947, 384.3880Gallagher, 6140 and Lucite, L.J. Intellectual Patterns of GiftedCompared with Average and Retarded Exualamel

Wechsler intelligence Scale for Children (WISC) 0 One hundred . visual-motor ability and other nonverbal skills* Furthermore, the exogenous child should . show more intertest and intratost variability than does the endogo