behavioral treatment and normal educational and intellectual functioning in \bung autistic children

7/29/2019 Behavioral Treatment and Normal Educational and Intellectual Functioning in \bung Autistic Children

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Journal ofConsulting andClinicalPsychology1987, Vol. 55, No. 1, 3-9 Copyright 1987by the American Psychological Association. Inc.0022-OC6X/87/J00.15

Behavioral Treatment and NormalEducational and IntellectualFunctioning in \bungAutistic Children

O. Ivar LovaasUniversity ofCalifornia, Los Angeles

Autism is a serious psychological disorder with onset in early childhood. Autistic children showminimal emotional attachment, absent or abnormal speech, retarded 1Q, ritualistic behaviors, ag-gression, and self-injury. The prognosis isvery poor, and medical therapieshave not proven effective.This articlereports the results of behavior modification treatment for two groups of similarlyconsti-tuted, youngautistic children. Follow-updata from an intensive, long-termexperimental treatmentgroup (n = 19) showed that 47% achieved normal intellectual and educational functioning, withnormal-range 1Q scoresand successful first grade performance inpublic schools. Another 40%weremildly retarded and assigned to special classes for the language delayed, and only 10%were pro-foundly retardedand assigned to classesfor the autistic/retarded.Incontrast, only2% of thecontrol-groupchildren(n = 40) achieved normal educational and intellectual functioning; 45% were mildlyretarded and placed in language-delayed classes, and 53% were severely retarded and placed in autis-tic/retardedclasses.

Kanner (1943) defined autistic children as children who ex-hibit (a) serious failure to develop relationships with other peo-ple before 30 months of age, (b) problems in development ofnormal language, (c) ritualistic and obsessional behaviors ("in-sistence on sameness"), and (d) potential for normal intelli-gence. A more complete behavioral definition has beenpro-videdelsewhere(Lovaas,Koegel, Simmons, & Long, 1973). Theetiology of autism is not known, and the outcome is very poor.In a follow-up study on young autistic children, Rutter (1970)reported that only 1.5% of his group(n =63) had achieved nor-mal functioning. About 35% showed fair or good adjustment,usually required some degree of supervision, experienced somedifficulties with people, had no personal friends, and showedminor oddities of behavior. The majority (more than 60%) re-mained severely handicapped and were living in hospitals formentally retarded orpsychotic individualsor inother protectivesettings. Initial IQ scoresappeared stable over time.Other stud-ies (Brown, 1969;DeMyeretal., 1973; Eisenberg, 1956; Free-man, Ritvo, Needleman, &Yokota, 1985; Havelkova, 1968) re-

This study was supported by Grant MH-11440 from the NationalInstitute of Mental Health. Aspects of this study were presented at the1982 convention of the American Psychological Association, Washing-ton, DC, by Andrea Ackerman, Paula Firestone, GayleGoldstein, Ron-ald Leaf, John McEachin, and the author. The authorexpresses hisdeepappreciation to the many undergraduate students at the University ofCalifornia, LosAngeles, who servedas student therapistson the project,to the many graduate students who served as clinic supervisors, and tothe manyparentswho trusted their children to our care.Special thanksto Laura Schreibman and Robert Koegel, who collaborated in the earlystages of this research project. Donald Baer, Bruce Baker, BradleyBucher, Arthur Woodward, and Haikang Shen provided statistical ad-vice and help in manuscriptpreparation. B. J. Freeman's helpinarrang-ingaccess to Control Group2 data isalso appreciated.

Correspondenceconcerning this article should beaddressedto O.IvarLovaas, Psychology Department, University of California, 405 HilgardAvenue, Los Angeles, California 900Z4.

port similar data. Higher scores on IQ tests, communicativespeech, and appropriate play areconsidered to beprognostic ofbetter outcome (Letter, 1967).

Medically and psychodynamically oriented therapies havenot proven effective in altering outcome (DeMyer, Hingtgen, &Jackson, 1981). No abnormal environmental etiology has beenidentified within the children's families (Letter, 1967). At pres-ent, themost promising treatment for autistic persons is behav-ior modification as derived from modern learning theory (De-Myer et al., 1981). Empirical results from behavioral interven-tion withautisticchildren have been both positiveand negative.On the positive side, behavioral treatment can build complexbehaviors, such as language, and can help to suppress pathologi-cal behaviors, such as aggression and self-stimulatory behavior.Clients vary widely in the amount of gains obtained but showtreatment gains in proportion to the time devoted to treatment.On the negative side, treatment gains have been specific to theparticular environment in which the client was treated, sub-stantial relapse has been observed at follow-up, and no clienthas been reported as recovered (Lovaas et al., 1973).

The present article reports a behavioral-intervention project(begun in 1970) that sought to maximizebehavioral treatmentgains by treating autistic children during most of their wakinghours for many years. Treatment included all significant per-sons in all significant environments. Furthermore, the projectfocused on very young autistic children (below the age of 4years) because it was assumed that younger children would beless likely to discriminate between environments and thereforemore likely to generalize and to maintain their treatment gains.Finally, it was assumed that it would be easier to successfullymainstream a very young autistic child into preschool than itwould be to mainstream an older autistic child into primaryschool.

It may be helpful to hypothesize an outcome of the presentstudy from a developmental or learning point ofview. One mayassume that normal children learn from their everyday environ-


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O. IVAR LOVAAS

ments most of their waking hours. Autisticchildren,conversely,do not learn from similarenvironments. Wehypothesized thatconstruction of a special, intense, and comprehensive learningenvironment for very youngautistic childrenwouldallow someof themto catch upwith their normal peersby first grade.

MethodSubjects

Subjects were enrolled for treatment if they met three criteria: (a)independent diagnosis of autism from a medical doctor or a licensedPhD psychologist, (b) chronological age (CA) less than 40 months ifmute and less than 46months if echolalic,and (c) prorated mentalage(PMA) of 11 monthsor more at a CA of 30 months. The last criterionexcluded 15% of the referrals.

The clinical diagnosis of autism emphasized emotional detachment,extreme interpersonal isolation, little if any toy or peer play, languagedisturbance (mutism or echolalia), excessive rituals, and onset in in-fancy. The diagnosis was based on a structured psychiatric interviewwith parents, onobservations of the child's free-play behaviors, onpsy-chological testing of intelligence, and on access to pediatric examina-tions. Overthe 15yearsof the project, the exact wordingof thediagnosischanged slightly in compliance with changesin the Diagnostic and Sta-tistical Manual of Menial Disorders (DSM-II1; American PsychiatricAssociation, 1980). During the last years, the diagnosis was made incompliance with DSM-III criteria (p. 87). Inalmost all cases, the diag-nosisof autism had been made prior to family contact with the project.Except for one case each in the experimental group and Control Group1,all caseswere diagnosed by staff of the Department of ChildPsychia-try, University of California, LosAngeles (UCLA) School of Medicine.Members of that staff have contributed to the writing of the DSM-IIIand to the diagnosis of autism adopted by the National Society for Chil-dren and Adults with Autism. If the diagnosisof autismwas not made,the casewas referred elsewhere. In other words, the project did not selectits cases. More than 90% of the subjects received two or more indepen-dent diagnoses, and agreement on the diagnosis of autism was 100%.Similarly high agreement was not reached for subjects who scoredwithin the profoundly retarded range on intellectual functioning(PMA < 11 months); these subjectswere excluded from the study.

Treatment ConditionsSubjects wereassigned to one of two groups: an intensive-treatment

experimental group (n - 19) that received more than 40hours ofone-to-onetreatment per week, or the minimal-treatment Control Group 1(n= 19) that received lOhoursor less of one-to-onetreatment perweek.Control Group 1 was used to gain further informationabout the rate ofspontaneous improvement in very young autistic children, especiallythose selected by the same agency that provided the diagnostic work-upfor the intensive-treatment experimental group. Both treatment groupsreceived treatment for 2 or more years. Strict random assignment (e.g.,based on acoin flip) to these groups could not be used due to parentprotest and ethical considerations. Instead, subjects were assigned tothe experimental group unless there was an insufficient numberof staffmembers available to render treatment (an assessment made prior tocontact with the family). Two subjects wereassigned to Control GroupI because they lived further away from UCLA than a 1 -hr drive, whichmade sufficient staffing unavailable to those clients. Because fluctua-tions in staff availability werenot associated in any waywith client char-acteristics,it was assumed that this assignment would produce unbiasedgroups. A large number of pretreatment measures werecollected totestthis assumption. Subjectsdid not change group assignment. Exceptfortwo familieswho left the experimental group within the first 6 months

(this group beganwith 21 subjects), all families stayed with their groupsfrom beginningto end.

AssessmentsPretreatment mental age (MA) scores were based on the following

scales (inorder of the frequency of their use): the Bayley Scales of InfantDevelopment (Bayley, 1955), the Cattell Infant Intelligence Scale (Cat-tell, 1960), theSunford-Binet Intelligence Scale(Thorndike, 1972), andthe Gesell Infant Development Scale (Gesell, 1949). The first threescales were administered to 90% of the subjects, and relative usage ofthese scaleswas similar in each group. Testing was carried out by gradu-atestudents inpsychologywho worked underthesupervisionofclinicalpsychologists at UCLA or licensed PhD psychologists at other agencies.The examiner chose the test that would best accommodate each sub-ject'sdevelopmental level, and this decision was reached independentlyof the project staff. Five subjects were judged to be untestable (3 in theexperimental group and 2 in Control Group I). Instead, the VinelandSocial Maturity Scale (Doll, 1953)was used to estimate theirMAs (withthe mother as informant). To adjust for variations in MA scores as afunction of the subject's CA at the time of test administration, PMAscores were calculated for a CA at 30 months (MA/CA X30).

Behavioral observations were based on videotaped recordings of thesubject's free-play behavior in a playroom equipped with several simpleearly-childhood toys. These videotaped recordings were subsequentlyscored for amount of (a) self-stimulatory behaviors, defined as pro-longed ritualistic, repetitive, and stereotyped behavior such as body-rocking, prolonged gazingat lights, excessive hand-flapping, twirling thebody as a top, spinning or lining of objects, and licking or smelling ofobjects or wall surfaces; (b) appropriate play behaviors, defined as thoselimiting the use of toys in the playroom to their intended purposes, suchas pushing the truck on the floor,pushing buttons on the toy cash regis-ter, puttinga record on therecord player,and banging withthe toyham-mer; and (c) recognizable words, defined to include any recognizableword, independent of whether the subject used it in a meaningful con-text or forcommunicative purposes.One observer who was naive aboutsubjects' group placement scored all tapes after being trained to agreewith twoexperienced observers (usingdifferent trainingtapes fromsim-ilar subjects). Interobserver reliability was scored on 20% of the tapes(randomly selected) and was computed for each category of behaviorfor each subject by dividing the sum of observer agreements by the sumof agreements and disagreements. Thesescores were then summed andaveraged across subjects. The mean agreement (based both on occur-rences and nonoccurrences)was 91% forself-stimulatory behavior,85%for appropriateplaybehavior,and 100% for recognizable words. Amoredetailed description of these behavioral recordings has been providedelsewhere(Lovaas et al., 1973).

A 1-hr parent interview about the subjects' earlier history providedsome diagnosticand descriptive information. Subjects received a scoreof 1foreach of the following variables parents reported:no recognizablewords; no toy play (failed to usetoys for their intended function); lack ofemotional attachment (failed torespond toparents' affection); apparentsensory deficit (parents had suspected their child to be blind or deafbecause the child exhibited no or minimal eye contact and showed anunusuallyhigh pain threshold): no peer play(subject did not show inter-active play with peers); self-stimulatory behavior; tantrums (aggressiontoward family members or self); and no toilet training. These 8 mea-sures from parents' intake interviews were summed to provide a sumpathology score. The intake interviewalso provided information aboutabnormal speech (0 = normal and meaningful language, however lim-ited; 1 = echolalic language used meaningfully [e.g., to express needs];2 = echolalia; and 3 = mute); age of walking; number of siblings inthe family; socioeconomic status of the father; sex; and neurologicalexaminations (including EEGs and CATscans) that resulted in findingsof pathology.Finally, CA at first diagnosis and at the beginningof the


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TREATMENT OF AUTISTIC CHILDRENpresent treatment wererecorded. This yielded atotal of 20 pretreatmentmeasures, 8 of whichwere collapsed into 1measure (sum pathology).

A brief clinical description of the experimental group at intake fol-lows (identical to that for Control Group 1): Only2 of the 19 subjectsobtained scores within the normal range of intellectual functioning; 7scored in the moderately retarded range, and 10scored in the severelyretarded range. No subject evidenced pretend or imaginaryplay, only2evidenced complex (several different or heterogeneous behaviors thattogether formed one activity) play, and the remaining subjects showedsimple (the same elementary but appropriate response made repeat-edly) play. One subject showed minimal appropriate speech, 7 wereecholalic, and 11 were mute. Accordingto the literature that describesthedevelopmental delaysof autistic children ingeneral, the autisticsub-jects in the present study constituted an average (or belowaverage) sam-ple of such children.

Posttreatment measures were recorded as follows: Between the agesof 6 and 7 years (when a subject would ordinarilyhave completed firstgrade), information about thesubjects' first-grade placement was soughtand validated; about the same time, an IQ score was obtained. Testingwascarried out by examiners who were naive about the subjects' groupplacement. Different scales were administered to accommodate differ-ent developmental levels. For example, a subject with a regular educa-tional placement received a Wechsler Intelligence Scale for Children-Revised (WISC-R; Wechsler, 1974) or a Stanford-Binet IntelligenceScale (Thorndike, 1972), whereas a subject in an autistic/retarded classreceived a nonverbal test like the Merrill-Palmer Pre-School Perfor-mance Test (Stutsman, 1948). In all instances of subjects havingachieved a normal IQ score, the testing was eventually replicated byother examiners. The scales (in order of the frequency of usage) in-cluded the WISC-R (Wechsler, 1974), the Stanford-Binet (Thorndike,1972), the Peabody Picture VocabularyTest (Dunn, 1981), the Wech-sler Pre-School Scale (Wechsler, 1967), the Bayley Scales of Infant De-velopment (Bayley, 1955), the Cattell Infant Intelligence Scale (Cattell,I960), and the Leiter International Performance Scale (Leiter, 1959).Subjects received a score of 3 for normalfunctioning if they received ascore on the WISC-Ror Stanford-Binet in the normal range, completedfirst grade in a normal class in a school for normal children, and wereadvanced to the second grade by the teacher. Subjects received a scoreof 2 if they were placed in first-grade in a smaller aphasia (languagedelayed, language handicapped, or learning disabled) class. Placementinthe aphasia class implied a higher level of functioningthan placementin classes for the autistic/retarded, but the diagnosis of autism was al-most always retained. Ascoreof 1 was given if the first-grade placementwas in a class for the autistic/retarded and if the child's IQ score fellwithin the severely retarded range.

Treatment ProcedureEach subject in the experimental group was assigned several well

trained student therapists who worked (part-time) with the subject inthe subject's home, school, and communityfor an averageof 40 hr perweek for 2 or more years. The parents worked as part of the treatmentteam throughout the intervention; they were extensively trained in thetreatment procedures so that treatment could take place for almost allof the subjects' waking hours, 365 days a year. Adetailed presentationof the treatment procedure has been presented in a teaching manual(Lovaas et al., 1980). The conceptual basis of the treatment was rein-forcement (operant) theory; treatment relied heavilyondiscrimination-learning data and methods. Various behavioral deficiencies were tar-geted, and separate programs were designed to accelerate developmentfor each behavior. High rates of aggressive and self-stimulatory behav-iors were reduced by being ignored; by the use of time-out; by the shap-ing of alternate, more socially acceptable formsof behavior; and (as alast resort) by the delivery of a loud "no" or a slap on the thigh contin-gent upon the presence of the undesirable behavior. Contingent physicalaversiveswere not used in the control group because inadequate staffing

in that group did not allow for adequate teaching of alternate, sociallyappropriate behaviors.

During the first year, treatment goals consisted ofreducingself-stimu-latory and aggressive behaviors, building compliance to elementary ver-bal requests, teaching imitation, establishing the beginnings of appro-priate toy play, and promoting the extension of the treatment into thefamily. The second year of treatment emphasized teaching expressiveand early abstract language and interactive play with peers. Treatmentwas also extended into the community to teach children to functionwithin a preschool group. The third year emphasized the teaching ofappropriate and varied expression of emotions; preacademic tasks likereading, writing, and arithmetic; and observationallearning (learningby observing other children learn). Subjects were enrolled only in thosepreschools where the teacher helped to carry out the treatment pro-gram. Considerable effort was exercised to mainstream subjects in anormal (average and public) preschool placement and to avoid initialplacement in special education classes with the detrimental effects ofexposuretootherautisticchildren. This occasionally entailed withhold-ing the subject's diagnosisofautism. Ifthechild became known as autis-tic (or as "a very difficult child") during the first year in preschool, thechild was encouraged to enroll in another, unfamiliar school (to startfresh). After preschool, placement inpublic education classeswasdeter-mined by school personnel. All children who successfully completednormal kindergarten successfully completedfirst grade and subsequentnormal grades. Children who were observed to be experiencing educa-tional and psychological problems received their school placementthrough Individualized Educational Plan (IEP) staffings (attended byeducatorsand psychologists) inaccordance with the Education For AllHandicapped Children Act of 1975.

All subjects who went on to a normal first grade were reduced intreatment from the 40 hr per week characteristic of the first 2 years to10 hr or less per week during kindergarten. After a subject had startedfirst grade, the project maintained a minimal (at most) consultant rela-tionship with some families. In two cases, this consultation and the sub-sequent correction of problem behaviors were judged to be essentialin maintaining treatment gains. Subjects who did not recover in theexperimental group received 40 hr or more perweek ofone-to-one treat-ment for more than 6 years (more than 14,000 hr of one-to-one treat-ment), with some improvement shown each year but with only 1 subjectrecovering.

Subjects in Control Group 1received the same kind of treatment asthose in the experimental group but with less intensity (less than 10hr of one-to-one treatment per week) and without systematic physicalaversives. In addition, these subjects received a variety of treatmentsfrom other sources in the community such as those provided bysmallspecial education classes.

Control Group 2consisted of 21 subjects selected from a larger group(N- 62) of young autistic children studied by Freeman et al. (1985).These subjects came from the same agency that diagnosed 95% of ourother subjects. Data from Control Group 2 helped to guard against thepossibility that subjectswho had been referred to us for treatment con-stituted a subgroup with particularly favorable or unfavorable out-comes. To provide a group of subjects similar to those in the experimen-tal group and Control Group 1, subjects for Control Group 2 werese-lected if they were 42 months old or youngerwhen first tested, had IQscores above 40 at intake, and had follow-up testing at 6 years of age.These criteria resulted in the selection of 21 subjects. Subjects in Con-trol Group 2 were treated like Control Group 1subjects but were nottreatedby the YoungAutismProject described here.

ResultsPretreatment Comparisons

Eight pretreatment variables from the experimental groupand Control Group 1 (CA at first diagnosis,CA at onset of treat-


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6 O. IVAR U3VAASTable1Means and F RatiosFrom Comparisons BetweenGroups on Intake Variables

GroupExperimentalControl 1

F*

Diagnosis CA32.035.3

1.58

Treatment CA34.640.94.02*

PMA18.817.11.49

Recognizablewords

.42

.58

.92

Toyplay28.220.22.76

Self-stimulation

12.119.63.37

Sumpathology

6.96.4.82

Abnormalspeech

2.42.2

.36>(. CA = chronological age; PMA = prorated mental age. Experimental group, n= 19;Control Group l ,n= 19.V/= 1,36.*p


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TREATMENT OF AUTISTIC CHILDRENTable3Educational Placement and Meanand RangeoflQ at Follow- Up

Group Recovered Aphasic Autistic/RetardedExperimental

NAflQRange

Control Group 1NMIQRange

Control Group2AA/IQRange

9107

94-1200

199

870

56-958

7430-102

1067

49-81

230 *1136

20-731044

35-54Note. Dashes indicate no scoreor no entry.* Both children received the samescore.

jects have remained stable. Only 2 subjects have been reclassi-fied: 1 subject (now 18 years old) was moved from an aphasiato a normal classroom after the sixth grade; 1subject (now 13years old) was moved from an aphasia to an autistic/retardedclass placement.

The MA and IQ scores of the two control groups remainedvirtually unchanged between intake and follow-up, consistentwith findings from other studies (Freeman et al., 1985; Rutter,1970). The stabilityof the IQscores of the young autistic chil-dren, as reported in the Freeman et al. study, is particularlyrelevant for the present study because it reduces thepossibilityof spontaneous recoveryeffects. Indescriptive terms, the com-bined follow-up data from the control groups show that theirsubjects fared poorly: Only 1 subject (2%) achieved normalfunctioning as evidenced by normal first-grade placement andan IQ of 99 on the WISC-R; 18 subjects (45%) werein aphasiaclasses (mean IQ = 70, range = 30-101);and 21 subjects (53%)wereinclasses for theautistic/retarded (meanIQ = 40, range =20-73). Table 3providesa convenient descriptive summaryofthe main follow-up data from the three groups.

Onefinal control procedure subjected 4 subjects in the exper-imental group (Ackerman, 1980) and 4 subjects in ControlGroup 1 (McEachin &Leaf, 1984) to a treatment interventioninwhich onecomponentof treatment (theloud "no" and occa-sional slap on the thigh contingent on self-stimulatory, aggres-sive,and noncompliant behavior) was at first withheld and thenintroduced experimentally. A within-subjects replication de-sign was used across subjects, situations, and behaviors, withbaseline observations varying from 3 weeks to 2 years aftertreatment had started (using contingent positive reinforcementonly). During baseline, when the contingent-aversive compo-nent was absent, small and unstable reductions were observedin the large amount of inappropriate behaviors, and similarsmall and unstable increases were observed in appropriate be-haviors such as play and language. These changes were insuffi-cient to allow for thesubjects' successful mainstreaming. Intro-duction ofcontingent aversives resulted in a sudden and stablereduction in the inappropriate behaviors and a sudden and sta-ble increase in appropriate behaviors. This experimental inter-vention helps to establish two points: First, at least onecompo-

nent in the treatment program functioned to produce change,which helps to reduce the effect of placebo variables. Second,this treatment component affected both the experimental andcontrol groups in a similar manner, supporting the assumptionthat the twogroupscontained similar subjects.

Analyses of variancewere carried out on the eight pretreat-ment variables to determine which variables, if any, were sig-nificantly related to outcome (gauged byeducational placementand IQ) in the experimental group and Control Group 1. Pro-rated mental age wassignificantly (p < .03) relatedtooutcomein both groups, a finding that is consistent with reports fromother investigators (DeMyeret al., 1981).Inaddition, abnormalspeech wassignificantly (p


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TREATMENT OF AUTISTIC CHILDREN

Although serious problems remain for exactly defining au-tism or identifying its etiology, one encouraging conclusion canbe stated: Given a group of children who show the kinds of be-havioral deficits and excesses evident in our pretreatment mea-sures, such children will continue to manifest similar severepsychological handicaps later in life unless subjected to inten-sive behavioral treatment that can indeed significantly alter thatoutcome.

These data promise amajor reduction in theemotional hard-ships of families with autistic children. The treatment proce-dures described here mayalsoproveequally effective with otherchildhood disorders, suchas childhood schizophrenia. Certainimportant, practical implications inthese findings mayalso benoted. The treatment scheduleofsubjects whoachieved normalfunctioning could be reduced from 40 hr perweekto infrequentvisits even after the first 2 years of treatment. The assignmentof one full-time special-education teacher for 2 years wouldcostan estimated $40,000, in contrast to the nearly $2 million in-curred (in direct costs alone) by each client requiring life-longinstitutionalization.

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behavioral treatment and normal educational and intellectual functioning in \bung autistic children

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