Diagnostic Interview for Social and Communication Disorders

Transcription

1 Diagnostic Interview for Social and Communication Disorders Synonyms DISCO Abbreviations ADI-R PDD Autism diagnostic interview-revised Pervasive developmental disorders Description The (DISCO) is a semistructured interview schedule used with the parent or carer of an individual to elicit a broad picture of the individual's behaviors and needs. Its primary purpose is to elicit information relevant to the autistic spectrum in order to assist clinicians in their judgment of an individual's level of development, disabilities, and specific needs. It contains sets of algorithms for diagnosis of autism according to the international classification criteria ( ICD and DSM) and other sets of diagnostic criteria. Key features of the DISCO are (a) that it can be used at any age, (b) that it collects extensive information not only on the core symptoms of autism but also beyond these symptoms (e.g., sensory symptoms, emotion symptoms, gross and fine motor skills, psychiatric and forensic problems, maladaptive behavior, sleep difficulties, etc.), and (c) that it has a strong developmental focus, including the detailed assessment of current developmental level and developmental delay. The (DISCO) is based on a concept of a spectrum of autistic disorders that predated the earliest ICD and DSM criteria for autism and pervasive developmental disorders (Wing, 1988, 1996; Wing & Gould, 1979). This concept is similar to, but wider than, the concept of pervasive developmental disorders (PDD) described in DSM-IV and ICD-10. Therefore, the use of the DISCO enables diagnosis of specific autism conditions according to DSM-IV and ICD-10, but the DISCO goes beyond this. Information collected is placed in a broad developmental and behavioral context that reflects a dimensional view of a spectrum of autistic disorder and emphasizes its broad-ranging nature. Therefore, an individual's difficulties with reciprocal social interaction, communication, and repetitive behavior can be understood against the pattern of their developmental skills and associated abilities and difficulties. In addition, symptoms of other related disorders (e.g., language, attention, or motor impairments) can be elicited for further investigation. Furthermore, as the DISCO is concerned with the assessment of needs as well as with the diagnosis of ASD, the information it collects is relevant for guiding recommendations relating to management and interventions. The DISCO interview schedule comprises more than 300 questions that are organized into eight parts. Part 1 provides a factual record of family, medical, and identifying information. Part 2 deals with the first 2 years of life. This infancy section consists of medical questions relevant to the diagnostic criteria for Rett's syndrome and a further set of questions relating to behaviors. Part 3 "Developmental Skills" forms the largest part of the DISCO. This section comprises subsections related to the following domains: (a) gross motor skills, (b) self-care, (c) domestic skills, (d) independence, (e) verbal and nonverbal communication, (f) social interaction with adults and peers, (g) social play and leisure, (h) imagination, (i) pictures, reading, and writing, (j) visuo-manual skills, and (k) cognitive skills. All the items are rated by the interviewer in terms of three aspects: (a) current level, (b) delay in acquiring relevant skills, and (c) untypical (or unusual) behavior associated with the relevant skills. The untypical behaviors cover both the past and present behaviors. Other parts of the DISCO also record both the past and present behavior patterns of the individual. Part 4 on repetitive activities includes subsections on stereotypies, atypical sensory responses, and repetitive routines. Part 5 on emotions includes questions on anxiety and mood changes. Part 6 on maladaptive behavior is concerned with behavior that impinges adversely on other people such as aggression and temper tantrums and disturbances of sleep. Part 8 on psychiatric conditions and forensic problems includes considerations of a range of psychiatric conditions relevant for 1

2 adolescents and adults that may need further investigations such as symptoms of schizophrenia, personality disorders, and eating disorders, and this part also includes specific subsections on catatonic features and sexual problems. Finally, there is a separate section (Part 7) to help guide clinicians to arrive at a clinical judgment independent of quantitative results. This part includes the interviewer's judgment on the quality of social interaction, social communication, social imagination, and overall pattern of activities. Whereas elsewhere during the interview, the aim is for the interviewer to establish the facts related to specific skills or behavior, in Part 7, the ratings are made on an overview of all the available information. This part of the schedule usually does not involve direct questioning of the informant and elicits judgments by the interviewer. As mentioned above, the DISCO enables diagnosis of specific autism conditions according to DSM-IV category "pervasive developmental disorders" ( American Psychiatric Association [APA], 1994) and the ICD-10 category "pervasive developmental disorders" ( World Health Organization [WHO], 1993). Selected items throughout the interview provide the diagnostic criteria not only for these diagnostic systems but also for other diagnostic systems. These diagnostic systems include (a) Kanner's early infantile autism (Kanner & Eisenberg, 1956), (b) Asperger's syndrome based on Gillberg and Gillberg (1989) (Ehlers & Gillberg, 1993; Wing, 1981), (c) autistic spectrum disorder (Wing & Gould, 1979), and (d) Wing and Gould's definition of social impairment. Completion of the entire interview takes approximately 2-3 h, and this provides a comprehensive picture of the individual's skills and abilities. This is particularly useful for complex cases. However, it is possible to adapt the DISCO for specific purposes. For example, in some cases, some sections may not be needed such as the section on medical/family information, where information may already be recorded, or the section on psychiatric conditions and forensic problems which applies to adolescents and adults. There may also be cases where the clinician needs only to obtain information on the current clinical picture, and therefore questions about delays in development and past behavior can be omitted. It is also possible to complete the interview using only items relevant for the diagnostic algorithms. The DISCO is distinctively different from other interview schedules, such as the Autism Diagnostic Interview-Revised (ADI-R) (Lord, Rutter, & Le Couteur, 1994), that were designed to be closely related to the ICD-10 research criteria for childhood autism ( WHO, 1993) and for DSM-IV autistic disorder ( APA, 1994). The DISCO is more detailed in the information it collects and is broader and more developmental in focus. For example, the interviewer collects information on a very large number of separate items each covering specific examples of types of behavior, from the most common to the rare, in order to facilitate the final clinical judgments. The interviewer also records the individual's current developmental level and their developmental delays for all domains of functioning. Finally, the interviewer can then apply a number of algorithms for different diagnostic systems using the DISCO. The DISCO can be used both clinically (see section "Clinical Uses" below) and for research. A number of research studies have been published using different data sets to examine its psychometric properties (see section "Psychometric Data" below). Research using the DISCO includes examination of its algorithms for Asperger's syndrome, for Wing and Gould's autistic spectrum disorder, and for ICD-10 childhood autism (Leekam et al., 2002; Leekam, Libby, Wing, Gould, & Gillberg, 2000). Research has also used the DISCO to investigate the role of associated sensory symptoms (Leekam et al., 2007), the adult outcomes of autism (Billstedt, Gillberg., & Gillberg, 2007; Cederlund et al., 2008), ASD symptoms and behavioral profiles in Rett's syndrome (Wulffaert et al., 2009a), Cornelia de Lange syndrome (Wulffaert et al., 2009), mild intellectual disability (Soenen et al., 2009), gender dysphoria (de Vries, Noens, Cohen-Kettenis, van Berckelaer-Onnes, & Doreleijers, 2010), fetal alcohol syndrome (Mukherjee, Layton, Yacoub, & Turk, 2011), and the link between epilepsy and autism symptoms (Danielsson, Gillberg, Billstedt, Gillberg, & Olsson, 2005;Turk et al., 2008). Epidemiological studies have also used the DISCO to study autism in adulthood (Brugha et al., 2011) and in the population of the Faroe Islands (Ellefsen et al., 2006). In addition, items within the DISCO have extracted to form research questionnaires and checklists for research purposes. These research measures have been used in studies of autism and typical populations. For example, a checklist has been used to investigate the empirical clustering of symptoms and cognitive abilities (Prior et al., 1998) and the relation between language delay and diagnosis (Eisenmajer et al., 1996) and a questionnaire used in the study of the development of repetitive behaviors (Leekam et al., 2007). Training for the DISCO has been developed by Dr. Judith Gould and Dr. Lorna Wing and consists of a 5-day training course in two stages. Training covers the Lorna Wing Centre's method of diagnosis, the complexities of diagnosis and assessment of needs, and the specialist psychological assessment. Stage 1 is for 3 days preceded by pre-course work and followed by evaluated interim coursework. Stage 2 is for 2 days leading to accreditation. A computer program is 2

3 available for accredited users. Training is available for clinicians involved in diagnosis and assessment of needs and for professionals who use DISCO for research. Information about training is available from the following address: Historical Background The origins of the DISCO are to be found in a study comparing children with autism with children with other disabilities (Down's syndrome, developmental receptive language disorders, developmental expressive language disorders, partial sight and partial hearing) and a group of children with typical development (Wing, 1969). The "Childhood Behavior Schedule," a questionnaire sent to parents by post, was designed for this study. It elicited information concerning the social, language, imagination, and motor impairments and the odd responses to sensory input and stereotyped behavior found in autism. These behaviors are now covered in much more detail in the DISCO. The original questionnaire schedule was reorganized and expanded to include items on developmental skills and was named the "Handicaps, Behavior, and Skills (HBS)" schedule. A variety of sources were used when constructing the developmental items, including Cooper, Moodley, and Reynell (1978), Doll (1965), Egan, Illingworth, and MacKeith (1969), Griffiths (1967), Sheridan (1973, 1977), and Williams and Kushlick (1970). The HBS was used for research in an epidemiological study of autism spectrum disorders in children in the former London Borough of Camberwell (Wing & Gould, 1979) and in a follow-up of the children into adult life (Wing, 1988). The original epidemiological study was designed to identify children with any of the features of autism in order to see if any clinical patterns could be discovered. This distinguished it from previous studies (e.g., Lotter, 1966, 1967) which looked specifically for children showing the narrow criteria originally suggested by Kanner and Eisenberg (1956). The DISCO interview schedule was developed from the HBS schedules for use in diagnostic work for both clinical work and research purposes. It was designed to include referrals with associated physical or psychiatric conditions or other developmental disorders such as dyslexia and dyspraxia. The schedule was developed to be relevant for all these variations in the clinical pictures. It has been expanded to include past behavior from infancy onward as well as for current state. It is also suitable for use with adults (see section on "Clinical Uses" below). Reliability and validity studies of the DISCO items were published in 2002 (see section on "Psychometric Data" below), when the ninth version was current (Leekam, Libby, Wing, Gould, & Taylor, 2002; Wing, Leekam, Libby, Gould, & Larcombe, 2002). The schedule has had two subsequent minor revisions and the current version is the eleventh revision and research has been published on both these versions (see "Psychometric Data" section). To date, research has been published using the algorithms of ICD-10 childhood autism, ICD-10 Asperger's syndrome, and ICD-10 atypical autism, Gillberg's Asperger's syndrome, and Wing and Gould's autism spectrum disorder (see Leekam et al., 2000 and Leekam et al., 2002). Research using the other algorithms - DSM-IIIR pervasive developmental disorders ( American Psychiatric Association, 1987), Kanner's and Eisenberg's criteria (Kanner & Eisenberg, 1956), and Wing and Gould's definition of social impairment - has not yet been published. Psychometric Data The psychometric properties of the DISCO have been examined in studies carried out in UK, in Sweden, and in Holland. The UK studies (Leekam et al., 2002; Wing et al., 2002) used DISCO-9 to carry out inter-rater reliability and validity analyses with data from 82 cases aged 3-11 years. Thirty-six had autistic spectrum disorder, 17 had learning disability, and 14 had language impairments. Inter-rater reliability was analyzed for over 400 items in the interview. Inter-rater reliability was high with kappa coefficient or intra-class correlation at.75 or higher for over 80% of the interview items. Analyses with the same sample examined two algorithms based on the ninth revision of the schedule (DISCO 9). Algorithm diagnoses were applied to interview items in order to analyze the relationship between clinical and algorithm diagnoses and the inter-rater reliability between interviewers for each algorithm output. Results showed that clinical diagnosis was significantly related to the diagnostic outputs for both algorithms and inter-rater reliability was high for both algorithms. The ICD childhood disorder algorithm produced more discrepant diagnoses than the Wing and Gould's autistic spectrum algorithm. Analysis of the ICD-10 algorithm items and combination of items helped to explain the reason for these discrepancies. The Swedish study (Nygren et al., 2009) used a translation of the tenth version of the DISCO (DISCO-10). Validity analysis compared DISCO-10-algorithm diagnoses with clinical diagnoses and with Autism Diagnostic Interview-Revised 3

4 (ADI-R) algorithm diagnoses in 57 cases of children and adults. Results showed good to excellent inter-rater reliability in 40 cases. The criterion validity was excellent when compared with clinical diagnoses and the ADI-R. The report concluded that although the DISCO-10 is not as widely used as the ADI-R, the evidence shows that it has the same level of psychometric credibility. The most recent psychometric research has been carried out by Maljaars, Noens, Scholte, and Berckelaur-Onnes ( 2011) using the Dutch translation of the DISCO-11. Their study included young children with different levels of intellectual disability (ID) including no ID, borderline, mild, moderate, and severe ID. DISCO algorithms for ICD-10 childhood autism and atypical autism were used in comparison with clinical classification and the Autism Diagnostic Observation Schedule ( ADOS; Lord et al., 1999) and Social Communication Questionnaire (SCQ: Rutter et al., 2003) to examine its criterion and convergent validity. Sensitivity and specificity of the DISCO were.96 and.79, respectively. Strong agreement was found between DISCO-11 and ADOS classification (k =.69, p <.001), although lower agreement was found with the SCQ (k =.49, p <.001). Comparisons with clinical diagnosis showed correct classification for the majority of cases with mismatches mainly explained by cases in the moderate and severe ID range. These results confirm that the DISCO has good criterion and convergent validity. This was especially the case for those with average intelligence or mild intellectual disability. However, the specificity was lower for those with moderate and severe levels of intellectual disability (IQ < 50), in line with previous findings. Clinical Uses The DISCO schedule can be used in clinical practice to fulfill three main purposes - to provide a clinical description, to make a clinical diagnosis, and to provide recommendations. First, it can be used to provide a clinical description by assisting the clinician in collecting information needed to compile a developmental history and a description of the present clinical picture. This information, including current level of development in everyday skills and the pattern of behavior, can be used as the basis of a narrative clinical report. Usually, the informant is someone who has known the person concerned from birth. However, when the DISCO is used with an adult and no informant is available to give an early history, the items of the DISCO schedule can be completed for current skills, deficits, and untypical behavior. Second, the DISCO can be used to assist in making a clinical diagnosis of autism spectrum disorders as well as of other disorders of development affecting social interaction and communication. Related to this purpose, the schedule can be used to run a number of different diagnostic algorithms according to different classification systems (see "Description" section earlier). In the case of an adult, where no developmental history is available, a diagnosis according to DSM and ICD is not possible, but the information gathered from the DISCO allows the experienced clinician to use their clinical judgment to make a working diagnosis in order to plan a management program. Finally, another important purpose of the DISCO is to provide information that will guide a clinician's recommendations concerning programs of education, adult support, and management of behavior. See Also Asperger, Hans Autism Diagnostic Observation Schedule Diagnostic Instruments in Autistic Spectrum Disorders Epilepsy Fetal Alcohol Syndrome ICD 10 Research Diagnostic Guidelines Intellectual Disability Kanner, Leo Rett's Syndrome Wing, Lorna References and Readings Billstedt, E., Gillberg, C., & Gillberg, C. (2007). Autism in adults, symptom patterns and early childhood predictors: Use of the DISCO in a community sample followed from childhood. Journal of Child Psychology and Psychiatry, 4

5 48(11), Brugha, T. S., McManus, S., Bankart, J., Scott, F., Purdon, S., Smith, J., et al. (2011). Epidemiology of autism spectrum disorders in adults in the community in England. Archives of General Psychiatry, 68(5), Danielsson, S., Gillberg, C., Billstedt, E., Gillberg, C., & Olsson, I. (2005). Epilepsy in young adults with autism: A prospective population-based follow-up study of 120 individuals diagnosed in childhood. Epilepsia, 46, de Vries, A. L. C., Noens, I. L. G., Cohen-Kettenis, P. T., van Berckelaer-Onnes, I. A., & Doreleijers, T. A. (2010). Autism spectrum disorders in gender dysphoric children and adolescents. Journal of Autism and Developmental Disorders, 40(8), Eisenmajer, R., Prior, M., Leekam, S., Wing, L., Ong, B., Gould, J., et al. (1998). Delayed language onset as a predictor of clinical symptoms in pervasive developmental disorders. Journal of Autism and Developmental Disorders, 28(6), Ellefsen, A., Kampmann, H., Billstedt, E., Gillberg, C., & Gillberg, C. (2007). Autism in the Faroe Islands: An epidemiological study. Journal of Autism and Developmental Disorders, 37, Leekam, S., Libby, S., Wing, L., Gould, J., & Gillberg, C. (2000). Comparison of ICD-10 and Gillberg's criteria for Asperger syndrome. Autism, 4(1), Leekam, S., Libby, S., Wing, L., Gould, J., & Taylor, C. (2002). Diagnostic interview for social and communication disorders: Algorithms for ICD-10 childhood autism and wing and Gould autistic spectrum disorder. Journal of Child Psychology and Psychiatry, 43, Leekam, S. R., Nieto, C., Libby, S., Wing, L., & Gould, J. (2007). Describing the sensory abnormalities of individuals with autism. Journal of Autism and Developmental Disorders, 37(5), Leekam, S., Tandos, J., McConachie, H., Meins, E., Parkinson, K., Wright, C., et al. (2007). Repetitive behaviours in typically developing 2-year-olds. Journal of Child Psychology and Psychiatry, 48(11), Maljaars, J., Noens, I, Scholte, E. & Berckelaur-Onnes, I. (2011). Evaluation of the criterion and convergent validity of the diagnostic interview for social and communication disorders in young and low-functioning children. Autism: International Journal of Research and Practice. Online June Mukherjee, R. A. S., Layton, M., Yacoub, R., & Turk, J. (2011). Autism and autistic traits in people exposed to heavy prenatal alcohol. Advances in Mental Health and Intellectual Disabilities, 5(1), Nygren, G., Hagberg, B., Billstedt, E., Skoglund, A., Gillberg, C., & Johannson, M. (2009). The Swedish version of the diagnostic interview for social and communication disorders (DISCO-10) psychometric properties. Journal of Autism and Developmental Disorders, 39(5), Prior, M., Eisenmajer, R., Leekam, S., Wing, L., Gould, J., Ong, B., et al. (1998). Are there subgroups within the autistic spectrum? A cluster analysis of a group of children with autistic spectrum disorders. Journal of Child Psychology and Psychiatry, and Allied Disciplines, 39(6), Turk, J., Bax, M., Williams, C., Amin, P., Eriksson, M., & Gillberg, C. (2008). Autism spectrum disorder in children with and without epilepsy: Impact on social functioning and communication. Acta Paediatrica, 98(4), Wing, L. (1969). The handicaps of autistic children: A comparative study. Journal of Child Psychology and Psychiatry, 10, Wing, L. (1988). The continuum of autistic characteristics. In E. Schopler & G. Mesibov (Eds.), Diagnosis and assessment in autism (pp ). New York: Plenum. Wing, L. (1996). The autistic spectrum. London: Constable. Wing, L., & Gould, J. (1979). Severe impairments of social interaction and associated abnormalities in children: Epidemiology and classification. Journal of Autism and Developmental Disorders, 9, Wing, L., Leekam, S., Libby, S., Gould, J., & Larcombe, M. (2002). Diagnostic interview for social and communication disorders: Background, inter-rater reliability and clinical use. Journal of Child Psychology and Psychiatry, 43,

6 Dr. Susan Leekam School of Psychology Cardiff University, Cardiff, UK DOI: URL: Part of: /_ Encyclopedia of Autism Spectrum Disorders Editor: Dr. Fred R. Volkmar PDF created on: December, 12, :50 6