Social Skills and Problem Behaviours in School Aged Children with High-Functioning Autism and Asperger s Disorder

Transcription

1 DOI /s ORIGINAL PAPER Social Skills and Problem Behaviours in School Aged Children with High-Functioning Autism and Asperger s Disorder Kathleen Macintosh Æ Cheryl Dissanayake Ó Springer Science+Business Media, Inc Abstract The social skills and problem behaviours of children with high-functioning autism and Asperger s Disorder were compared using parent and teacher reports on the Social Skills Rating System. The participants were 20 children with high-functioning autism, 19 children with Asperger s Disorder, and 17 typically developing children, matched on chronological and overall mental age. The children with autism and Asperger s Disorder were not differentiated on any social skill or problem behaviour based either on teacher or parent report. However, both clinical groups demonstrated significant social skill deficits and problem behaviours relative to the typically developing children, and the original standardization sample. The findings were compatible with the view that autism and Asperger s Disorder belong on a single spectrum of disorder. Keywords High-functioning autism Æ Asperger s Disorder Æ Social skills Æ Problem behaviours Æ SSRS Introduction Extensive similarities in the characteristic features associated with Autistic Disorder and Asperger s Disorder have resulted in an ongoing debate as to whether or not these conditions represent distinct diagnostic entities, or are, K. Macintosh Æ C. Dissanayake (&) School of Psychological Science, La Trobe University, Melbourne, Victoria 3086, Australia c.dissanayake@latrobe.edu.au instead, part of the same spectrum of disorders (Bishop, 1989; Gillberg, 1989; Klin, Volkmar, & Sparrow, 2000, Macintosh & Dissanayake, 2004). Resolution of this controversy is important in clarifying the etiology, prognosis, and appropriate interventions for Autistic Disorder and Asperger s Disorder, and determining the validity of current diagnostic systems. According to current classification systems (DSM-IV; American Psychiatric Association, APA, 1994; ICD-10; World Health Organisation, WHO, 1993), Asperger s Disorder can only be diagnosed in the absence of an intellectual disability. Thus, in order for Asperger s Disorder to be considered a unique diagnostic category, it must be distinguishable from high-functioning autism (that is, autism without an associated intellectual disability) (Klin et al., 2000; Macintosh & Dissanayake, 2004; Schopler, Mesibov, & Kunce, 1998). Comparative research on the similarities and differences between Asperger s Disorder and high-functioning autism has focused on cognitive and neuropsychological skills, language and communication abilities, motor skills, medical and developmental histories, course and outcome, and to a limited extent core symptoms such as restricted, repetitive behaviours, and social development. In their recent review of the relevant literature, Macintosh and Dissanayake (2004) indicate that there is increasing evidence of a substantial overlap between the disorders in many of these areas of functioning, which supports the view that they belong on the same autism spectrum. However, firm conclusions about the diagnostic validity of Asperger s Disorder as separate from autism have not been possible due to variations in methodology, inconsistent findings between studies, flaws in research design, and the paucity of research on some key areas that require examination in order to resolve the diagnostic controversy.

2 Macintosh and Dissanayake (2004) indicate that whilst a deficit in social interaction skills is recognized in the clinical literature as a key symptom of both high-functioning autism and Asperger s Disorder, limited comparative research has been undertaken on social behaviour. The research conducted to date (Gillberg, 1989; Ozonoff, South, & Miller, 2000; Szatmari, Archer, Fisman, Streiner, & Wilson, 1995; Szatmari, Bartolucci, & Bremner, 1989; Szatmari, Bremner, & Nagy, 1989) has suggested that both clinical groups show gross impairments in the area of social functioning in comparisons with non-handicapped peers. However, many similarities have been found between the clinical groups. For example, on the basis of parent report, Szatmari and colleagues (Szatmari et al., 1989, 1995; Szatmari, Tuff, Allen, Finlayson, & Bartolucci, 1990) found that young children with high-functioning autism and Asperger s Disorder are comparable in their engagement in eye contact during social exchanges, participation in conversation, use of non-verbal gestures and facial expressions, use of comfort-giving acts, and involvement in joint activities and social play with others. When group differences have emerged, these have tended to be in the direction of people with Asperger s Disorder displaying more advanced social skills than those with autism such as in acts of greeting, egalitarianism and joy in social interactions, social responsiveness to adults, a sharing of their interests, affection towards parents, and an interest in peers. Eisenmajer et al. (1996) and Gillberg (1989) both found that people with high-functioning autism and Asperger s Disorder had similarly developed skills in making and maintaining friendships, although those with Asperger s Disorder showed a greater interest in having friends. On the basis of retrospective parent report, Ozonoff et al. (2000) found that Asperger s Disorder was associated with greater social competence relative to high-functioning autism at the age of 4 5 years, but this difference was no longer apparent at the time of the study when participants were aged 6 21 years. Furthermore, the groups could not be distinguished on the basis of observed deficits in social interaction, as assessed in a clinical setting. Although the studies reviewed above provide important information about the precise social deficits and competencies associated with high-functioning autism and Asperger s Disorder, further investigation into their social abilities is crucial in contributing to the resolution of the controversy over the diagnostic differentiation between the two disorders. On the basis of clinical descriptions, the criteria, as presented in DSM-IV (APA, 1994) regarding the social impairments in Autistic Disorder and Asperger s Disorder, are identical (Volkmar & Klin, 2000). However, the nature and extent of the similarities and differences in social functioning needs to be more fully established through empirically based evidence (Gillberg & Ehlers, 1998; Kugler, 1998; Szatmari, 1998). In view of the limited research on social functioning amongst individuals with high-functioning autism and Asperger s Disorder, Macintosh and Dissanayake (2006; see also Dissanayake & Macintosh, 2003) undertook a detailed analysis of the spontaneous social interactions between primary-school aged children with high-functioning autism and Asperger s Disorder and their typically developing peers in a school-yard setting. They found few differences in the patterns of social interaction between children with these disorders, with the exception that the children with Asperger s Disorder were more often engaged in conversation and made more social bids towards their peers than those with autism. The two clinical groups were similar to a control sample of typically developing children on several variables, such as the frequency of participation in some forms of social activity (i.e., observing others, parallel play, and complementary play), the rates of social initiations, the frequency with which language and non-verbal gestures were used in interactions, and the frequency with which social exchanges were categorized as positive/prosocial/neutral, or aggressive/negative in quality. Nevertheless, the overall proportion of the observation sessions that was spent by the two clinical groups in social interactions was significantly lower, such that they were more often alone relative to their typically developing peers. The study reported by Macintosh and Dissanayake (2006) was part of a broader research program in which both teachers and parents reports of social skills and problem behaviours were collected using the Social Skills Rating System (SSRS; Gresham & Elliot, 1990), to supplement the observational data. The findings from this aspect of the research program are described in the current paper. The SSRS examines a number of social skills, specifically co-operation, assertiveness, responsibility, and self-control, that are important predictors of social competence. It also measures several problem behaviours, namely, externalizing and internalizing symptoms, and hyperactivity, that may impede the development or performance of necessary social skills. The SSRS has been found to correlate significantly with comparable measures including the Social Behaviour Assessment (Stephens, 1978), the Harter Teacher Rating Scale (Harter, 1985), and Achenbach s Child Behaviour Checklist (Achenbach & Edelbrock, 1983). Ozonoff et al. (2000) also examined social skills using the SSRS in their study of individuals with high-functioning autism and Asperger s Disorder, and reported no differences in parental reports of social skills. The current study expands upon their research findings by comparing participants from the two clinical populations on each of

3 the sub-scales of the SSRS that assess social competencies, as well as the overall social skills domain. In addition, the problem behaviour domain of the SSRS was also investigated. Furthermore, social skills and problem behaviours were investigated from the perspectives of both parents and teachers. In gathering information from both parents and teachers, the SSRS permits the collection of complementary information about children s social functioning across a range of contexts, including the home, community and school. Whilst parents have extensive and long-term knowledge about their own children across several contexts, teachers perspectives are based on an understanding of typical child development, allowing them to make comparisons between the child s behaviour with that of his peers. As the majority of children in Australia with high-functioning autism and Asperger s Disorder are integrated into mainstream schools, the opportunity for comparisons between their social behaviour, and that of their typically developing peers, is both available and useful. Such comparisons make it possible to determine precisely how the social development of these children deviates from and is consistent with the norm. Externalizing and internalizing behavioural problems, measurable through the SSRS, were also considered important to examine. An increased prevalence of such difficulties has been reported amongst children and adolescents with high-functioning autism and Asperger s Disorder, and it is likely that such problem behaviours directly interfere with their ability to enter into and sustain mutually enjoyable peer relations (Eisenmajer et al., 1996; Frea, 1995; Green, Gilchrist, Burton, & Cox, 2000; Kim, Szatmari, Bryson, Streiner, & Wilson, 2000; Koegel, Koegel, Frea, & Smith, 1995, Szatmari et al., 1989; Tantam, 2000; Tonge, Brereton, Gray, & Einfeld, 1999). The aim in the study reported here was to determine the differences and similarities in the social skills and behaviour problems of children with high-functioning autism and Asperger s Disorder, from both their parents and teachers perspectives, relative to each other and also to their typically developing peers. In so doing, the results will expand our knowledge about the social difficulties and competencies associated with these conditions, as well as informing the debate on whether these conditions are discrete diagnostic entities, or are part of the same autism spectrum. As indicated, prior comparative research on the social development of individuals with high-functioning autism and Asperger s Disorder has revealed few differences and many similarities, especially with increasing age. Where differences have existed in their social abilities, these have tended to be in the direction of children with autism demonstrating less social competence than those with Asperger s Disorder (e.g., Dissanayake & Macintosh, 2003; Eisenmajer et al., 1996; Gillberg, 1989; Macintosh & Dissanayake, 2006; Ozonoff, Rogers, & Pennington, 1991; Ozonoff et al., 2000; Szatmari et al. 1989, 1990, 1995). Given these findings, it was predicted that the children with high-functioning autism would be rated by both caregivers as having comparable social skills in the areas of cooperation, assertiveness, responsibility, and self-control, relative to the children with Asperger s Disorder. However, should differences between the clinical groups be apparent, the children with Asperger s Disorder were expected to show greater skill development in these areas than those with autism. To date, there has been little comparative research on problem behaviors amongst children with high-functioning autism and Asperger s disorder. However, active but odd (Wing & Gould, 1979) modes of interacting, characterized by a tendency to initiate social exchanges, but in a naïve, socially inappropriate or domineering manner, as well as aggressive styles of relating with others, have been portrayed as more typical of Asperger s Disorder than high-functioning autism (Frith, 1991; Klin & Volkmar, 1997; Tonge et al., 1999; Wing, 1996). In view of this, it was predicted that the children with Asperger s Disorder would be rated by teachers and parents as having more problem behaviours than the children with autism. It was also predicted that the children in the two clinical groups would have fewer social skills and more problem behaviours according to both teachers and parents reports relative to a control group of typically developing peers. Method Participants The participants included 20 children with high-functioning autism, 19 children with Asperger s Disorder, and 17 typically developing children. All children were male and aged between 4 years, 4 months and 10 years, 10 months. The participants attended mainstream primary schools, except for three typically developing children who attended preschool. The children in the clinical groups had been diagnosed by experienced clinical psychologists/psychiatrists using strict DSM-IV (APA, 1994) criteria for Autistic Disorder and Asperger s Disorder. The children with Autistic Disorder were required to have a history of significant impairments in language functioning, whilst exclusion of clinically significant delays in language development was necessary for the diagnosis of Asperger s Disorder. Clinical records and developmental histories were examined closely in order to substantiate the diagnoses made.

4 In order to exclude children with an intellectual disability, all participants were required to have a Full Scale IQ (FSIQ) greater than 70, as assessed using the short-form of the Stanford-Binet Intelligence Scales (Fourth Edition; Thorndike, Hagen, & Sattler, 1986). This abbreviated battery includes the Vocabulary, Pattern Analysis, Bead Memory, and Quantitative sub-tests from the domains of Verbal Reasoning, Abstract/Visual Reasoning, Short-Term Memory, and quantitative reasoning, respectively. The FSIQ was determined by calculating the Area Standard Age Score for each domain and then adding these scores together. Reliability of the Composite Score for the fourtest abbreviated battery is good, with Kuder Richardson Formula 20 co-efficients ranging from.92 to.96 for the age group of participants in this study. The Stanford Binet Intelligence Scales were chosen over other measures of intelligence as it is the only one that encompassed the entire age range of the participants. Sample characteristics are provided in Table 1. The three groups were matched on chronological age (CA: F (2, 53) = 2.293, P =.111) and overall mental age (MA: F (2, 53) = 1.436, P =.247). The groups were not matched on Verbal MA (VMA: F (2, 53) = 4.352, P =.018) which was calculated from performance on the vocabulary, comprehension and absurdities sub-tests on the Stanford- Binet. Post hoc analyses revealed that the typically developing children had a higher Verbal MA than participants with high-functioning autism (P =.017). The remaining pairwise comparisons were not significant (P >.1). The three groups were also significantly different from each other on the FSIQ (F (2, 53) = , P <.001). There were no group differences on the socio-demographic variables obtained from families, with regard to parents ages, education levels, occupations, and the number of hours spent in paid employment. Families were also matched on the background variables of ethnicity, preferred language, and household composition. In each Table 1 Sample characteristics Variable HFA (n = 20) AsD (n = 19) TD (n = 17) Mean CA in (19.54) (20.20) (19.84) months (SD) Range Mean overall MA (17.56) (25.57) (23.92) in months (SD) Range Mean verbal MA (18.39) (26.67) (23.37) in months (SD)* Range Mean FSIQ (SD) ** (11.06) (14.17) (9.70) *P <.05. **P <.01 group, most families were English-speaking (HFA: 95%; AsD: 100%; TD: 100%), of anglo-australian background (HFA: 84.2%; AsD: 70.6%; TD: 71.4%), and comprised two-parent households (HFA: 90%; AsD: 94.1%; TD: 88.2%). The only relevant group difference in terms of major life events related to whether or not there had been a change in schools during the prior 2-year period, F (2, 52) = 5.089, P =.010. Both children with high-functioning autism (P =.010) and Asperger s Disorder (P =.053) were more likely to have changed schools than the typically developing children. The variables of New School and Verbal MA were used as co-variates in the statistical analyses where appropriate, as it appeared reasonable, on theoretical grounds, to anticipate that relationships may exist between a child s status on these two variables and on the measures of social skills and problem behaviours examined in this study. Measures The Social Skills Rating System The SSRS (Elementary Level; Gresham & Elliott, 1990) was used to obtain teachers and parents reports of the children s social skills and adaptive functioning. For the few typically developing children at kindergarten (n = 3), the Preschool Level form was used. The SSRS is a standardized questionnaire that measures the perceived frequency with which certain social skills are displayed at school or in the home and community. The SSRS also examines problematic behaviours that may impede the development or performance of necessary social skills. The Teacher version also examines academic competence. This domain was not analysed given its limited relevance to this study. In the Teacher version of the SSRS, 30 items assess Social Skills relevant to a classroom environment and 18 items assess Problem Behaviours. The Parent form contains 55 questions; 38 items measure Social Skills pertaining to home and community settings, and 17 relate to Problem Behaviours. In both Teacher and Parent versions of the SSRS, the Social Skills domain contains the sub-scales of Co-operation, Assertion, and Self-Control. The Parent form includes an additional sub-scale of Responsibility. The Co-operation sub-scale assesses behaviours such as sharing, assisting others, and complying with rules and instructions. Items on the Assertion sub-scale measure behaviours such as requesting information from others, introducing one self, and responding to the behaviours of others. The Self-Control sub-scale examines behaviours such as appropriately managing teasing, engaging in turn-taking, and developing compromises. The Responsibility sub-scale includes behaviours such as effectively

5 communicating with adults, completing household chores, and showing regard for others property. The Problem Behaviours domain assesses Externalizing and Internalizing problems, and Hyperactivity. The sub-scale of Externalizing includes items measuring physical or verbal aggression towards others, poor anger management, and arguing. The Internalizing sub-scale examines behaviours suggestive of sadness, anxiety, low self-esteem and loneliness. Items in the Hyperactivity subscale (which is only included in the Elementary Level forms) assess acts involving excessive motion, impulsiveness, and distractibility. For both Teacher and Parent versions of the SSRS, respondents rate the frequency of behaviours in the Social Skills and Problem Behaviours categories on a three point scale; Never, Sometimes and Very Often, which correspond to scores of zero, one, and two respectively. Raw scores for each sub-scale on both the Teacher and Parent forms of the SSRS were obtained by summing the scores for each item in that sub-scale. The Total raw score for each domain was determined by adding together the raw scores for the relevant sub-scales. On the basis of comparisons with the standardization sample of nonhandicapped males of primary-school age, standard scores and percentile rankings for the Social Skills and Problem Behaviours scales were calculated, based on the Total raw scores for these domains (Gresham & Elliot, 1990). The SSRS has been found to have acceptable internal consistency, test retest and inter-rater reliability, and content, construct, discriminant, and criterion-related validity (Gresham & Elliott, 1990). There is low convergent validity between the Parent and Teacher forms, but this is not unexpected as children s social behaviour varies across contexts, and items within the SSRS are not identical for the two versions (Gresham & Elliot, 1990). Procedure Participants and their parent(s) attended two sessions at the Child Development Unit at La Trobe University during which each child s cognitive abilities were assessed. The parents were provided with a socio-demographic information form and the SSRS (Parent form) to complete, and written consent was given for the child s teacher to complete the SSRS. The Teacher form was subsequently distributed to each child s classroom teacher, and collected within the next two weeks. Results Separate analyses were planned for the Social Skills and Problem Behaviours domains of the SSRS, given that they measured different aspects of social functioning. As the Preschool and Elementary versions of the SSRS are not comparable on the Problem Behaviours domain, the data obtained from the three typically developing kindergarten children were excluded for all analyses relating to this domain. Correlations between Teacher and Parent Reports Pearson Product-Moment (and Spearman Rank) correlations between teacher and parent ratings were calculated on the corresponding sub-scales and standard scores of the SSRS to determine the extent of concordance between their reports. Correlations on the raw scores obtained for each sub-scale and on the standard scores were determined both for each group separately and on overall scores collapsed across groups (see Table 2). As there is no equivalent of the Responsibility sub-scale on the Teacher form, this variable was excluded from the correlation analysis. Table 2 shows that except for Assertion and Hyperactivity, the correlations between teachers and parents reports were generally modest. As there was little justification for claiming redundancy of information from the two sources, the data obtained on the SSRS from both teachers and parents was analysed for group differences. Differences One-way multivariate analyses of variance/covariance (MANOVAs/MANCOVAs), using one or both the co-variates (New School and Verbal MA) as appropriate, were used on each of the domain sub-scales in order to test for group differences in Social Skills and Problem Behaviours. The variables of Internalizing and Hyperactivity from the Problem Behaviours domain of the SSRS Table 2 Correlation coefficients between teacher and parent ratings on the Social Skills and Problem Behaviours domains of the SSRS SSRS Domain HFA (n = 20) AsD (n = 19) TD (n = 17) Overall (n = 56) Social Skills Co-operation Assertion.10.60*.58*.65*** Self-Control * Standard Score * Problem Behaviours Externalizing * Internalizing ** Hyperactivity.98***.98***.97***.95*** Standard Score a *P <.05. **P <.01. ***P <.001 a Spearman Rank correlation coefficients are provided in this row

6 (Teacher form) required transformation in order to satisfy the normality assumption of the statistical analyses. Given violation of the homogeneity of variance assumption in relation to the Problem Behaviours sub-scales of Externalizing (Parent form) and Hyperactivity (Parent and Teacher form), a conservative two-tailed alpha level of.025 was used in analyzing the significance of test results for these variables (Tabachnick & Fidell, 2001). One-way analyses of variance/covariance (ANOVAs/ANCOVAs) were conducted on the standard scores for the Social Skills and Problem Behaviours domains. As the distribution of the Problem Behaviours Standard Scores (Teacher form) was skewed and not amenable to improvement through transformation, a Kruskal Wallis one-way ANOVA was performed on this variable. The data presented in Figs. 1 4 are taken prior to any transformations in order to enhance the interpretability of the findings. For variables subjected to ANCOVA or MANCOVA, the means (and SE) have been adjusted for the effects of one or both co-variates as appropriate. SSRS Social Skills Domain Teachers Reports A MANCOVA was conducted on the sub-scales of the Social Skills domain using Verbal MA as a covariate (see Fig. 1 and Table 3) revealed a significant multivariate main effect of Diagnostic. differences were apparent for each of the Social Skills subscales. Post hoc analyses indicated a similar pattern of findings for each type of social skill. According to teacher report, the typically developing children demonstrated significantly higher levels of Co-operation, Assertion, and Self-Control compared to the children with high-functioning autism and Mean Raw Score HFA (n = 20) AsD (n = 18) TD (n = 17) Co-operation Assertion Self-Control Responsibility Social Skills Sub-Scales (Parent Form) Fig. 2 Mean raw scores on the Social Skills sub-scales of the SSRS (Parent form) Asperger s Disorder, who were rated as comparable in their exhibition of all three Social Skills. These findings were further substantiated when a oneway ANCOVA was performed on the Social Skills Standard Score. The Mean Standard Scores (SD in brackets), adjusted for effects of the covariate, were (12.26), (11.61), and (12.06) for the autism, Asperger s Disorder, and typically developing groups respectively. The main effect of Diagnostic on this global measure of social functioning, F(2, 47) = , P <.001, was again accounted for by differences between the clinical groups and the typically developing children (typically developing versus autism: P <.001; typically developing versus Asperger s Disorder: P <.001). No difference was found between the children with highfunctioning autism and Asperger s Disorder (P =.692). There was no significant main effect of the covariate, F(1,47) = 1.374, P = HFA (n = 18) AsD (n = 17) TD (n = 16) 10 8 HFA (n = 19) AsD (n = 17) TD (n = 15) Mean Raw Score Mean Raw Score Co-operation Assertion Self-Control Social Skills Sub-Scales (Teacher Form) 0 Externalizing Internalizing Hyperactivity Problem Behaviour Sub-Scales (Teacher Form) Fig. 1 Mean raw scores on the Social Skills sub-scales of the SSRS (Teacher form) Fig. 3 Mean raw scores on the Problem Behaviours sub-scales of the SSRS (Teacher form)

7 10 HFA (n = 19) AsD (n = 17) TD (n = 15) Table 4 MANCOVA results for the Social Skills Sub-Scales of the SSRS (Parent version) Source Variable F df P Mean Raw Score Parents Reports Externalizing Internalizing Hyperactivity Problem Behaviour Sub-Scales (Parent Form) Fig. 4 Mean raw scores on the Problem Behaviours sub-scales of the SSRS (Parent form) Parents reports of Social Skills for the three groups of children largely replicated the teachers reports (See Fig. 2 and Table 4). The MANCOVA again revealed overall differences associated with group membership for parents reports of Social Skills. There was also a significant main effect of the covariate New School, but not of the Verbal MA covariate. With the exception of Responsibility, each of the social skills contributed to the main effect of Diagnostic. The parents responses, in accordance with teachers, indicated that the typically developing children were perceived as more co-operative and assertive than either children with high-functioning autism or Asperger s Disorder. Contrary to teachers ratings of Self-Control, parents responses failed to yield a significant difference between the typically developing children and the Asperger s Disorder group. However, the typically developing Table 3 MANCOVA results for the Social Skills Sub-Scales of the SSRS (Teacher version) Source Variable F df P Covariates Verbal.943 3, MA Diagnostic , 90 <.001 Social Skill F df P differences Co-operation , TD > HFA (P =.047) TD > AsD (P =.008) HFA = AsD (P =.557) Assertion , 47 <.001 TD > HFA (P = <.001) TD > AsD (P = <.001) HFA = AsD (P =.992) Self-Control , 47 <.001 TD > HFA (P = <.001) TD > AsD (P = <.001) HFA = AsD (P =.072) Covariates Verbal , MA New , School Diagnostic , 94 <.001 Social Skill F Df P differences Co-operation , TD > HFA (P =.001) TD > AsD (P =.002) HFA = AsD (P =.792) Assertion , 50 <.001 TD > HFA (P =. <.001) TD > AsD (P = <.001) HFA = AsD (P =.721) Self-Control , TD > HFA (P =.012) TD = AsD (P =.110) HFA = AsD (P =.249) Responsibility , NS children were rated as showing more Self-Control in volatile social situations than those with a diagnosis of autism. Once again, no differences were found between the clinical groups in relation to each of these social skills. A one-way ANCOVA was conducted on the Standard Score for the Social Skills domain of the SSRS. The Mean Standard Scores (with standard deviations), after adjustment for the covariate, were (15.51) for the autism group, (15.18) for the Asperger s Disorder group, and (16.06) for the typically developing group. There was a slight main effect of the covariate, F(1, 51) = 3.936, P =.053, and differences were detected as a function of Diagnostic, F(2, 51) = 8.434, P =.001, such that the typically developing children were rated as more socially competent by parents than participants with autism (P <.001) and Asperger s Disorder (P =.002). The overall social skills, as reported by parents, of the two clinical samples were not significantly different from one another (P =.449). SSRS Problem Behaviours Domain Teachers Reports The typically developing children, who demonstrated the greatest social skills, showed a relative paucity of problem behaviours. The converse was true for both clinical groups; reduced social skills were accompanied by more severe problem behaviours (see Fig. 3 and Table 5). The MANOVA undertaken on the sub-scales of the Problem Behaviours domain revealed a significant multivariate group difference on Problem Behaviours based on teachers reports. This effect was attributable to differences

8 Table 5 MANOVA results for the Problem Behaviours Sub-Scales of the SSRS (Teacher version) Source Variable F df P Diagnostic , 86 <.001 Problem F df P Differences Behaviour Internalizing , 45 <.001 TD < HFA (P = <.001) TD < AsD (P = <.001) HFA = AsD (P =.702) Externalizing , NS Hyperactivity , 45 <.001 TD < HFA (P = <.001) TD < AsD (P =.003) HFA = AsD (P =.231) Table 6 MANOVA results for the Problem Behaviours Sub-Scales of the SSRS (Parent version) Source Variable F df P Diagnostic , Problem F df P Differences Behaviour Internalizing , 48 <.001 TD < HFA (P =.002) TD < AsD (P = <.001) HFA = AsD (P =.399) Externalizing , NS Hyperactivity , TD < HFA (P = <.001) TD < AsD (P =.001) HFA = AsD (P =.824) between the groups on Internalizing symptoms and Hyperactivity. Again, there were differences between the typically developing children and each of the clinical samples, but a lack of differentiation between children with autism and Asperger s Disorder, on Internalizing symptoms and Hyperactivity. Although not reaching significance, a similar trend was apparent for Externalizing behaviour problems. The Kruskal Wallis one-way ANOVA on the Problem Behaviours Standard Score (Teacher form) confirmed the significant differences associated with Diagnostic, v 2 (2) = , P <.001. The Mean Standard Scores (SD in brackets) were (9.83) for the autism group, (10.21) for the Asperger s Disorder group, and (8.91) for the typically developing group. The Mean Ranks were (high-functioning autism), (Asperger s Disorder), and (typically developing). The typically developing children showed substantially lower overall behaviour problems compared to the children in the clinical groups, who presented as remarkably similar in the severity of their challenging behaviours, when assessed globally. Parents Reports The MANOVA performed on the sub-scales of the Problem Behaviours domain, based on parents ratings (see Fig. 4 and Table 6), revealed an effect of Diagnostic. Significant group differences were found in relation to Internalizing symptoms and Hyperactivity. The patterns of group differences, based on parental perceptions, replicated those found when examining teachers ratings of problem behaviours, such that the children with autism and Asperger s Disorder were viewed by parents as showing substantially more Internalizing symptoms and Hyperactivity relative to the typically developing children. The children with clinical diagnoses were comparable in the extent to which they demonstrated such symptoms. Although not significant, the same general trend was observed with regard to Externalizing behaviour problems. The Mean Standard Scores (SD in brackets) for the three groups on the Problem Behaviours Standard Score (Parent form) were: (15.68) for the autism group, (14.85) for the Asperger s Disorder group, and (9.94) for the typically developing group. The oneway ANOVA revealed a significant group difference, F(2, 48) = , P <.001, that was, once again, due to differences between the typically developing group and each of the clinical groups According to parents reports, the typically developing children had substantially fewer overall behaviour problems than children with either autism (P <.001) or Asperger s Disorder (P <.001), who did not differ significantly from each other (P =.605). Comparisons of Social Skills and Problem Behaviours with the Standardization Sample The finding that children with high-functioning autism and Asperger s Disorder demonstrated severe social skills deficits and problem behaviours compared to the group of typically developing children in this study raised the question of how clinically meaningful these differences were in relation to the general population. In an effort to clarify the extent to which the social skills and problem behaviours of the three groups deviated from the norm, the scores were compared with those for the original standardization sample of non-handicapped male primary school children (Gresham & Elliot, 1990). On the basis of comparisons with the standardization sample, the SSRS allows the individual s level of each social skill and problem behaviour to be determined. That is, for each sub-scale and overall domain, the child is classified as usually demonstrating fewer, an average number, or more examples of the particular social skill or problem behaviour.

9 Social Skills Domain Comparisons of the scores obtained by children in the two clinical groups on the Social Skills domain with those for the original standardization sample confirmed the findings based on comparisons with the typically developing children. That is, relative to both samples of typically developing age-matched children, the participants with high-functioning autism and Asperger s Disorder had fewer social skills (see Table 7). In the case of the autism group, mean ratings indicated below average demonstration of each social skill, with one exception (i.e., teachers report of Co-operation). In contrast, there was some discrepancy in how the social skills of the Asperger s Disorder group were rated, depending on the informant. Whilst, as a group, children with Asperger s Disorder were classified as having average skills in Co-operation and Self-Control on the basis of teachers reports, parents reports suggested that at home and in community settings these skills were demonstrated less often than is characteristic of typically developing peers. In contrast to both clinical groups, the typically developing children demonstrated age-appropriate levels of each specific social skill. Problem Behaviours Domain Once again, the finding of severe problem behaviours in children with high-functioning autism and Asperger s Disorder was substantiated when scores on the SSRS were examined against norms for the general population of male Table 7 Level of each Social Skill on the SSRS relative to the standardization sample of non-handicapped male primary school children Social Skill HFA (n = 18) AsD (n = 17) TD (n = 16) Co-operation Teacher Average Average Average Parent Fewer Fewer Average Assertion Teacher Fewer Fewer Average Parent Fewer Fewer Average Responsibility Teacher Parent Fewer Fewer Average Self-Control Teacher Fewer Average Average Parent Fewer Fewer Average Total Teacher Fewer Average Average Parent Fewer Fewer Average Note: The n values provided represent the minimum sample size for any sub-scale. The n values were higher for some sub-scales Table 8 Level of each Problem Behaviour on the SSRS relative to the standardization sample of non-handicapped male primary school children Problem Behaviour primary school children. (See Table 8). In contrast to the group of typically developing children who showed average levels of all behaviour problems, the autism group was reported by parents as displaying excessive Hyperactivity and more problem behaviours overall relative to the norm. Teachers differed in reporting that the autism group showed average levels of Hyperactivity and also rated the overall problem behaviours of this group as slightly less severe than parents. A tendency towards some extreme problem behaviours was also apparent for the Asperger s Disorder group in that at least one informant revealed the existence of more Internalizing symptoms, Hyperactivity and behaviour problems overall than would be typical of same-age peers. Discussion HFA (n = 19) AsD (n = 17) TD (n = 15) Externalizing Teacher Average Average Average Parent Average Average Average Internalizing Teacher Average Average More Average Parent Average Average Average Hyperactivity Teacher Average Average More Average Parent More More Average Total Teacher Average More Average Parent More More Note: The n values provided represent the minimum sample size for any sub-scale. The n values were higher for some sub-scales In accordance with the hypotheses, the teachers and parents reports indicated that primary-school aged children with high-functioning autism and Asperger s Disorder showed deficits in the social skills of co-operation, assertion and self-control across a variety of real-life settings relative to their typically developing peers. The teachers and parents reports were also concordant in describing the children with autism and Asperger s Disorder as having substantially more problems with both hyperactivity and internalizing symptoms compared to the typically developing children. The high level of congruence in the findings from the reports of parents and teachers is noteworthy given the generally low correlations between the responses of these informants on the sub-scales of the SSRS. Indeed, given the different contexts in which teachers and parents interact

10 with children, their varying levels of experience with children generally, and the fact that there was no direct correspondence between the items on the two versions of the SSRS, high correlations between their responses were not anticipated (Gresham & Elliott, 1990). However, the finding of a consensus between these adults in judging the social skills and problem behaviours of the children with clinical diagnoses as significantly deviating from normal, suggests that in relation to each group as a whole, both informants were similarly capable of recognizing abnormalities in behaviour. This is despite the fact that they may differ to some extent in their perceptions of the specific social functioning of individual children. Comparisons between the scores obtained on the SSRS and the standardized norms for the general population of male primary school children (see Gresham & Elliott, 1990) confirmed the severity of the social skill deficits and, to a lesser extent, the problem behaviours experienced by the children in each of the clinical groups. The occurrence of extreme internalizing and hyperactivity symptoms was common amongst both the participants with highfunctioning autism and Asperger s Disorder. Thus, based on comparisons with both the typically developing control children in this study and the original SSRS standardization sample, the prediction of reduced social skills and greater problem behaviours in children with high-functioning autism and Asperger s Disorder relative to the norm was supported. These difficulties with key social skills and behaviour problems may be reflected in the reduced rates of peer interaction found during observation of these children in the school-yard (Macintosh & Dissanayake, 2006). The finding of an increased frequency of behaviour problems amongst the clinical groups is consistent with the results from studies indicating that children and adolescents with high-functioning autism and Asperger s Disorder are vulnerable to conditions such as depression, anxiety, Oppositional Defiant Disorder and Attention Deficit Hyperactivity Disorder (Eisenmajer et al., 1996; Green et al., 2000; Kim et al., 2000; Szatmari et al., 1989; Tantam, 2000; Tonge et al., 1999). Together, these findings may be interpreted as evidence that primary school-aged children, as well as adolescents and adults with highfunctioning autism and Asperger s Disorder, are often troubled and frustrated by their poor social competence. Alternatively, inappropriate behaviours may be strategies the child has developed to achieve desired social responses, in the absence of more socially appropriate or conventional methods. It is highly probable that these problem behaviours adversely affect children s ability to develop satisfactory peer interactions (Frea, 1995; Green et al., 2000; Koegel, Koegel, Frea, & Smith, 1995; Macintosh & Dissanayake, 2006; Matson et al., 1996; Tonge et al., 1999; Zwaigenbaum & Szatmari, 1999). In accordance with the hypothesis, the children with high-functioning autism and Asperger s Disorder were indistinguishable in their levels of co-operation, assertion, responsibility, and self-control as reported both by teachers and parents. These findings are compatible with those from the observational data, collected as part of the broader study incorporating the same children, in revealing very few differences in the nature or frequency of their participation in a range of social activities and behaviours (Dissanayake & Macintosh, 2003; Macintosh & Dissanayake, 2006). The findings are also concordant with Ozonoff et al. s (2000) finding of no differences between children and adolescents with high-functioning autism and Asperger s Disorder on the social skills domain of the SSRS. Therefore, the findings from Ozonoff et al. s study and those from the current investigation are highly corroborative in indicating that once children with high-functioning autism and Asperger s Disorder reach primary school age, they show similar social impairments. Contrary to prediction, there was no evidence that the children with Asperger s Disorder showed more problem behaviours compared to the children with high-functioning autism. The two clinical groups were, once again, highly comparable on teacher and parent reports of their behaviour problems, with both demonstrating elevated rates of such symptoms relative to the typically developing children. Although the current study was not designed to examine psychopathology in children with high-functioning autism and Asperger s Disorder, the results on the Problem Behaviours domain of the SSRS are compatible with the findings of several other researchers in indicating that youth with these disorders are at an increased risk of co-morbid internalizing and externalizing psychological symptoms. The current finding that children with highfunctioning autism and Asperger s Disorder of primary school age are similar in the severity of their internalizing symptoms is commensurate with Kim et al. s (2000) results. These researchers found that children and adolescents with these conditions were comparable on parent report measures of depression and anxiety. In contrast, Tonge et al. (1999) found, also on the basis of parent report, that symptoms of anxiety as well as anti-social and disruptive behaviour problems were significantly more prevalent amongst youth with Asperger s Disorder than those with autism. Eisenmajer et al. (1996) likewise indicated that children and adolescents diagnosed with Asperger s Disorder were more likely to have Attention Deficit Hyperactivity Disorder than youth given a diagnosis of high-functioning autism.

11 The studies of both Eisenmajer et al. (1996) and Tonge et al. (1999) differed from the present research and that of Kim et al. s (2000) study in that they used a mix of children, adolescents and young adults as participants. It is possible that the group difference found by Eisenmajer et al. and Tonge et al. related to the inclusion of participants in their mid-adolescent and early adult years. The current findings and those of Kim et al. suggest that during their middle childhood years, the risk of co-morbid behavioural and emotional disturbances is comparable for children with high-functioning autism and Asperger s Disorder. It may be that with increasing age, there is some divergence between the groups in the probability of such problems developing, such that adolescents and adults with Asperger s Disorder are at significantly greater risk of experiencing behavioural and/or emotional disorders. In summary, the findings from the current investigation suggest that there are few differences between primaryschool aged children with high-functioning autism and Asperger s Disorder in the frequency with which they display several key social skills and internalizing and externalizing behaviour problems, according to both their teachers and parents. Thus, there was little evidence that any of the social deficits or skills addressed in this study is specific to one or other condition. The current findings are therefore consistent with many other recent studies (Macintosh & Dissanayake, 2004) in being most supportive of the view that autism and Asperger s Disorder are variants of the same underlying syndrome. Nevertheless, given the low sample size, and limited age range and gender of participants (all male), the applicability of the current findings to individuals of both sexes and at different stages of the life cycle needs to be established through replication studies. The implication of the current findings for clinical practice is that the category of Autism Spectrum Disorder or an equivalent term be used to replace the separate diagnoses of Autistic Disorder and Asperger s Disorder (DSM-IV, APA, 1994; ICD 10, WHO, 1992). The criteria for Autism Spectrum Disorder could be structured in a manner consistent with a multi-dimensional and developmental approach to diagnosis, whereby the particular manifestation of core symptoms and status regarding associated key features is detailed for each individual (Szatmari, 1998; Volkmar, 1998; Volkmar & Klin, 2000; Wing, 2000). On the basis of the current findings, it seems likely that, at least for primary school-aged children, similar social skills interventions are likely to be appropriate for children with both high-functioning autism and Asperger s Disorder. Thus, programs that have been empirically validated as useful for children with high-functioning autism, involving approaches such as modeling, prompting and reinforcing appropriate social behaviours, are also likely to be valuable for children with Asperger s Disorder (see Charlop-Christy & Kelso, 1999; Gray, 1998; Hall, 1997; Quill, 1995). For both groups, interventions may need to include strategies for enhancing the specific social skills of co-operation, assertiveness, and self-control. The current research findings also suggest that both primary school-aged children with high-functioning autism and Asperger s Disorder are at heightened risk of externalizing and internalizing behavioural and emotional disturbance. Such problems clearly need to be assessed for and addressed in intervention programs (Koegel & Koegel, 1995; Quill, 1995). Definitive conclusions about how comparable interventions should be for children with high-functioning autism and Asperger s Disorder are not justified until further research is undertaken in order to determine the nature and extent of similarities and differences between these children in micro-level social behaviours that were not possible to examine in this study. It is likely that such micro-level social behaviours (e.g., eye contact, facial expressions, content of discourse) will need to be closely examined through structured experimental and observational research. Furthermore, intervention studies in which the outcomes of various therapeutic strategies are compared for the two groups of children are needed in order to establish the extent to which similar intervention programs are appropriate for them. References Achenbach, T., & Edelbrock, C. (1983). Manual for the child behavior checklist and revised child behavior profile. Burlington, VT: University of Vermont Department of Psychiatry. American Psychiatric Association. (1994). Diagnostic and statistical manual of mental disorders (4th ed.). Washington, DC: American Psychiatric Association. Bishop, D. V. M. (1989). Autism, Asperger s syndrome and semanticpragmatic disorder: Where are the boundaries? British Journal of Disorders of Communication, 24, Charlop-Christy, M. H., & Kelso, S. E. (1999). Autism. In V. L. Schwean & D. H. Saklofske (Eds.), Handbook of psychosocial characteristics of exceptional children (pp ). New York: Kluwer Academic/Plenum Publishers. Dissanayake, C., & Macintosh, K. (2003). Mind reading and social functioning in children with Autistic disorder and Asperger s disorder. In B. Repacholi & V. Slaughter (Eds.), Individual differences in theory of mind: Implications for typical and atypical development (pp ). New York: Psychology Press. Eisenmajer, R., Prior, M., Leekam, S., Wing, L., Gould, J., Welham, M., & Ong, B. (1996). 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