Annual Research Review: Re-thinking the classification of autism spectrum disorders
Catherine Lord
Center for Autism and the Developing Brain, Weill-Cornell Medical College and New York Presbyterian Hospital/Westchester Division, White Plains, NY, USA
Search for more papers by this authorRebecca M. Jones
Center for Autism and the Developing Brain, Weill-Cornell Medical College and New York Presbyterian Hospital/Westchester Division, White Plains, NY, USA
Search for more papers by this authorCatherine Lord
Center for Autism and the Developing Brain, Weill-Cornell Medical College and New York Presbyterian Hospital/Westchester Division, White Plains, NY, USA
Search for more papers by this authorRebecca M. Jones
Center for Autism and the Developing Brain, Weill-Cornell Medical College and New York Presbyterian Hospital/Westchester Division, White Plains, NY, USA
Search for more papers by this authorConflicts of interest statement: No conflicts declared.
Abstract
Background: The nosology of autism spectrum disorders (ASD) is at a critical point in history as the field seeks to better define dimensions of social-communication deficits and restricted/repetitive behaviors on an individual level for both clinical and neurobiological purposes. These different dimensions also suggest an increasing need for quantitative measures that accurately map their differences, independent of developmental factors such as age, language level and IQ.
Method: Psychometric measures, clinical observation as well as genetic, neurobiological and physiological research from toddlers, children and adults with ASD are reviewed.
Results: The question of how to conceptualize ASDs along dimensions versus categories is discussed within the nosology of autism and the proposed changes to the DSM-5 and ICD-11. Differences across development are incorporated into the new classification frameworks.
Conclusions: It is crucial to balance the needs of clinical practice in ASD diagnostic systems, with neurobiologically based theories that address the associations between social-communication and restricted/repetitive dimensions in individuals. Clarifying terminology, improving description of the core features of ASD and other dimensions that interact with them and providing more valid and reliable ways to quantify them, both for research and clinical purposes, will move forward both practice and science.
References
- Aldridge, F.J., Gibbs, V.M., Schmidhofer, K., & Williams, M. (2012). Investigating the Clinical Usefulness of the Social Responsiveness Scale (SRS) in a Tertiary Level, Autism Spectrum Disorder Specific Assessment Clinic. J Autism Dev Disord, 42(2), 294–300.
- Aman, M.G., Singh, N.N., Stewart, A.W., & Field, C.J. (1985). Psychometric characteristics of the aberrant behavior checklist. Am J Ment Defic, 89(5), 492–502.
- American Psychiatric Association (1987). Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition. Washington DC: American Psychiatric Association.
- American Psychiatric Association (1994). Diagnostic and statistical manual of mental disorders, 4th edn . Washington, DC: American Psychiatric Association.
- American Psychiatric Association (2000). Task force on DSM-IV. Diagnostic and statistical manual of mental disorders: DSM-IV-TR. Washington, DC: American Psychiatric Association.
- American Psychiatry Association (2012). DSM-5 development. Available from: http://www.dsm5.org [last accessed 16 January 2012].
- Anderson, D.K., Maye, M.P., & Lord, C. (2011). Changes in maladaptive behaviors from midchildhood to young adulthood in autism spectrum disorder. Am J Intellect Dev Disabil, 116(5), 381–397.
- Anderson, J.S., Nielsen, J.A., Froehlich, A.L., DuBray, M.B., Druzgal, T.J., Cariello, A.N., … & Lainhart, J.E. (2011). Functional connectivity magnetic resonance imaging classification of autism. Brain, 134(Pt 12), 3742–3754.
- Anderson, D.K., Oti, R.S., Lord, C., & Welch, K. (2009). Patterns of growth in adaptive social abilities among children with autism spectrum disorders. J Abnorm Child Psychol, 37(7), 1019–1034.
- Baird, G.. (2012). What did parents want? National Autism Society Parent Survey. Paper presented at conference: Autism spectrum disorder: from clinical practice to educational provision, January 12/13, 2012. Available from: http://www.conference.ie/Conferences/index.asp?Conference=144. Slides of presentation available from: http://www.conference.ie/content/BairdG.ppt [last accessed 16 February 2012].
- Baird, G., Charman, T., Pickles, A., Chandler, S., Loucas, T., Meldrum, D., … & Simonoff, E. (2008). Regression, developmental trajectory and associated problems in disorders in the autism spectrum: The SNAP study. J Autism Dev Disord, 38(10), 1827–1836.
- Baron-Cohen, S. (2009). The short life of a diagnosis. The New York Times. Available from: http://www.nytimes.com/2009/11/10/opinion/10baron-cohen.html [last accessed 16 February 2012].
- Baron-Cohen, S., Leslie, A.M., & Frith, U. (1985). Does the autistic child have a “theory of mind”? Cognition, 21(1), 37–46.
- Bertrand, J., Mars, A., Boyle, C., Bove, F., Yeargin-Allsopp, M., & Decoufle, P. (2001). Prevalence of autism in a United States population: The Brick Township, New Jersey, investigation. Pediatrics, 108(5), 1155–1161.
- Berument, S.K., Rutter, M., Lord, C., Pickles, A., & Bailey, A. (1999). Autism screening questionnaire: Diagnostic validity. Br J Psychiatry, 175, 444–451.
- de Bildt, A., Oosterling, I.J., van Lang, N.D., Sytema, S., Minderaa, R.B., van Engeland, H., … & de Jonge, M.V. (2011). Standardized ADOS scores: Measuring severity of autism spectrum disorders in a Dutch sample. J Autism Dev Disord, 41(3), 311–319.
- Bishop, D.V. (1989). Autism, Asperger’s syndrome and semantic-pragmatic disorder: Where are the boundaries? Br J Disord Commun, 24(2), 107–121.
- Bishop, D.V.. (2003). Autism and specific language impairment: Categorical distinction or continuum? Novartis Found Symp, 251, 213–226; discussion 226–234, 281–297.
- Bishop, D.. (2011). How common is autism? Notes & Theories blog on guardian.co.uk (7 June 2011). Available from: http://www.guardian.co.uk/science/blog/2011/jun/07/how-common-autism-diagnosis [last accessed 16 February 2012].
- Bishop, S., Gahagan, S., & Lord, C. (2007). Re-examining the core features of autism: A comparison of autism spectrum disorder and fetal alcohol spectrum disorder. J Child Psychol Psychiatry, 48(11), 1111–1121.
- Bishop, D.V., & Norbury, C.F. (2002). Exploring the borderlands of autistic disorder and specific language impairment: A study using standardised diagnostic instruments. J Child Psychol Psychiatry, 43(7), 917–929.
- Bishop, S.L., Richler, J., & Lord, C. (2006). Association between restricted and repetitive behaviors and nonverbal IQ in children with autism spectrum disorders. Child Neuropsychol, 12(4-5), 247–267.
- Black, M., Freeman, B.J., & Montgomery, J. (1975). Systematic observation of play behavior in autistic children. J Autism Child Schizophr, 5, 363–371.
- Bodfish, J.W., Symons, F.J., Parker, D.E., & Lewis, M.H. (2000). Varieties of repetitive behavior in autism: Comparisons to mental retardation. J Autism Dev Disord, 30(3), 237–243.
- Bolton, P.F., Pickles, A., Murphy, M., & Rutter, M. (1998). Autism, affective and other psychiatric disorders: Patterns of familial aggregation. Psychol Med, 28(2), 385–395.
- Bowler, D.M. (1992). “Theory of mind” in Asperger’s syndrome. J Child Psychol Psychiatry, 33(5), 877–893.
- Brieber, S., Neufang, S., Bruning, N., Kamp-Becker, I., Remschmidt, H., Herpertz-Dahlmann, B., … & Konrad, K. (2007). Structural brain abnormalities in adolescents with autism spectrum disorder and patients with attention deficit/hyperactivity disorder. J Child Psychol Psychiatry, 48(12), 1251–1258.
- Carey, B. (2012). New definition of autism may exclude many, study suggests. The New York Times, A1.
- Carr, T., & Lord, C. (2012). Perceived negative impact in African American and Caucasian mothers of children with autism spectrum disorder. Autism.
- Carter, A.S., Messinger, D.S., Stone, W.L., Celimli, S., Nahmias, A.S., & Yoder, P. (2011). A randomized controlled trial of Hanen’s ‘More Than Words’ in toddlers with early autism symptoms. J Child Psychol Psychiatry, 52(7), 741–752.
- Charman, T., Baird, G., Simonoff, E., Loucas, T., Chandler, S., Meldrum, D., & Pickles, A. (2007). Efficacy of three screening instruments in the identification of autistic-spectrum disorders. Br J Psychiatry, 191, 554–559.
- Charman, T., Jones, C.R., Pickles, A., Simonoff, E., Baird, G., & Happe, F. (2011). Defining the cognitive phenotype of autism. Brain Res, 1380, 10–21.
- Cicchetti, D.V., Koenig, K., Klin, A., Volkmar, F.R., Paul, R., & Sparrow, S. (2011). From Bayes through marginal utility to effect sizes: A guide to understanding the clinical and statistical significance of the results of autism research findings. J Autism Dev Disord, 41(2), 168–174.
- Constantino, J.N., Davis, S.A., Todd, R.D., Schindler, M.K., Gross, M.M., Brophy, S.L., … & Reich, W. (2003). Validation of a brief quantitative measure of autistic traits: Comparison of the social responsiveness scale with the autism diagnostic interview-revised. J Autism Dev Disord, 33(4), 427–433.
- Constantino, J.N., & Gruber, C.P. (2005). Social Responsiveness Scale manual. Los Angeles: Western Psychological Services.
- Constantino, J.N., Lavesser, P.D., Zhang, Y., Abbacchi, A.M., Gray, T., & Todd, R.D. (2007). Rapid quantitative assessment of autistic social impairment by classroom teachers. J Am Acad Child Adolesc Psychiatry, 46(12), 1668–1676.
- Constantino, J.N., Przybeck, T., Friesen, D., & Todd, R.D. (2000). Reciprocal social behavior in children with and without pervasive developmental disorders. J Dev Behav Pediatr, 21(1), 2–11.
- Constantino, J.N., & Todd, R.D. (2003). Autistic traits in the general population: A twin study. Arch Gen Psychiatry, 60(5), 524–530.
- Constantino, J.N., Zhang, Y., Frazier, T., Abbacchi, A.M., & Law, P. (2010). Sibling recurrence and the genetic epidemiology of autism. Am J Psychiatry, 167(11), 1349–1356.
- Contrucci Kuhn, S.A., & Triggs, M. (2009). Analysis of social variables when an initial functional analysis indicates automatic reinforcement as the maintaining variable for self- injurious behavior. J Appl Behav Anal, 42(3), 679–683.
- Coutanche, M.N., Thompson-Schill, S.L., & Schultz, R.T. (2011). Multi-voxel pattern analysis of fMRI data predicts clinical symptom severity. Neuroimage, 57(1), 113–123.
- Croen, L.A., Grether, J.K., Hoogstrate, J., & Selvin, S. (2002). The changing prevalence of autism in California. J Autism Dev Disord, 32(3), 207–215.
- Cuccaro, M.L., Shao, Y., Grubber, J., Slifer, M., Wolpert, C.M., Donnelly, S.L., … & Pericak-Vance, M.A. (2003). Factor analysis of restricted and repetitive behaviors in autism using the Autism Diagnostic Interview-R. Child Psychiatry Hum Dev, 34(1), 3–17.
- Dalton, K.M., Nacewicz, B.M., Johnstone, T., Schaefer, H.S., Gernsbacher, M.A., Goldsmith, H.H., … & Davidson, R.J. (2005). Gaze fixation and the neural circuitry of face processing in autism. Nat Neurosci, 8(4), 519–526.
- Dawson, G., Rogers, S., Munson, J., Smith, M., Winter, J., Greenson, J., … & Varley, J. (2010). Randomized, controlled trial of an intervention for toddlers with autism: The Early Start Denver Model. Pediatrics, 125(1), e17–e23.
- Dawson, G., Webb, S.J., & McPartland, J. (2005). Understanding the nature of face processing impairment in autism: Insights from behavioral and electrophysiological studies. Dev Neuropsychol, 27(3), 403–424.
- Dominick, K.C., Davis, N.O., Lainhart, J., Tager-Flusberg, H., & Folstein, S. (2007). Atypical behaviors in children with autism and children with a history of language impairment. Res Dev Disabil, 28(2), 145–162.
- Donno, R., Parker, G., Gilmour, J., & Skuse, D.H. (2010). Social communication deficits in disruptive primary-school children. Br J Psychiatry, 196(4), 282–289.
- Drew, A., Baird, G., Taylor, E., Milne, E., & Charman, T. (2007). The social communication assessment for toddlers with autism (SCATA): An instrument to measure the frequency, form and function of communication in toddlers with autism spectrum disorder. J Autism Devl Disord, 37(4), 648–666.
- Ecker, C., Marquand, A., Mourao-Miranda, J., Johnston, P., Daly, E.M., Brammer, M.J., … & Murphy, D.G. (2010). Describing the brain in autism in five dimensions--magnetic resonance imaging- assisted diagnosis of autism spectrum disorder using a multiparameter classification approach. J Neurosci, 30(32), 10612–10623.
-
Ellis, E.M., & Thal, D.J. (2008). Early language delay and risk for language impairment.
Perspect Lang Learn Educ, 15(3), 93–100.
10.1044/lle15.3.93 Google Scholar
- Elsabbagh, M., Mercure, E., Hudry, K., Chandler, S., Pasco, G., Charman, T., … & Johnson, M.H. (2012). Infant neural sensitivity to dynamic eye gaze is associated with later emerging autism. Curr Biol, 22, 1–5.
- Esbensen, A.J., Seltzer, M.M., Lam, K.S., & Bodfish, J.W. (2009). Age-related differences in restricted repetitive behaviors in autism spectrum disorders. J Autism Dev Disord, 39(1), 57–66.
- Fischbach, G.D., & Lord, C. (2010). The Simons Simplex Collection: A resource for identification of autism genetic risk factors. Neuron, 68(2), 192–195.
- Folstein, S., & Rutter, M. (1977). Infantile autism: A genetic study of 21 twin pairs. J Child Psychol Psychiatry, 18(4), 297–321.
- Fombone, E. (2002). Prevalence of childhood disintegrative disorder. Autism, 6(2), 149–157.
- Fombonne, E. (2003). Epidemiological surveys of autism and other pervasive developmental disorders: An update. J Autism Dev Disord, 33(4), 365–382.
- Frith, U., & Happe, F. (1994). Autism: Beyond “theory of mind”. Cognition, 50(1-3), 115–132.
- Geschwind, D.H. (2011). Genetics of autism spectrum disorders. Trends Cogn Sci, 15(9), 409–416.
- Gillespie-Lynch, K., Sepeta, L., Wang, Y., Marshall, S., Gomez, L., Sigman, M., & Hutman, T. (2012). Early childhood predictors of the social competence of adults with autism. J Autism Dev Disord, 42(2), 161–174.
- Gjevik, E., Eldevik, S., Fjaeran-Granum, T., & Sponheim, E. (2011). Kiddie-SADS reveals high rates of DSM-IV disorders in children and adolescents with autism spectrum disorders. J Autism Dev Disord, 41(6), 761–769.
- Gotham, K., Pickles, A., & Lord, C. (2009). Standardizing ADOS scores for a measure of severity in autism spectrum disorders. J Autism Dev Disord, 39(5), 693–705.
- Gotham, K., Risi, S., Dawson, G., Tager-Flusberg, H., Joseph, R., Carter, A., … & Lord, C. (2008). A replication of the Autism Diagnostic Observation Schedule (ADOS) revised algorithms. J Am Acad Child Adolesc Psychiatry, 47(6), 642–651.
- Gotham, K., Risi, S., Pickles, A., & Lord, C. (2007). The Autism Diagnostic Observation Schedule: Revised algorithms for improved diagnostic validity. J Autism Dev Disord, 37(4), 613–627.
- Green, J., Charman, T., McConachie, H., Aldred, C., Slonims, V., Howlin, P., … & Pickles, A. (2010). Parent-mediated communication-focused treatment in children with autism (PACT): A randomised controlled trial. Lancet, 375(9732), 2152–2160.
- Guilmatre, A., Dubourg, C., Mosca, A.L., Legallic, S., Goldenberg, A., Drouin-Garraud, V., … & Campion, D. (2009). Recurrent rearrangements in synaptic and neurodevelopmental genes and shared biologic pathways in schizophrenia, autism, and mental retardation. Arch Gen Psychiatry, 66(9), 947–956.
- Guttmann-Steinmetz, S., Gadow, K.D., & Devincent, C.J. (2009). Oppositional defiant and conduct disorder behaviors in boys with autism spectrum disorder with and without attention-deficit hyperactivity disorder versus several comparison samples. J Autism Dev Disord, 39(7), 976–985.
- Happe, F.. (2011). Why fold asperger syndrome into autism spectrum disorder in the DSM-5?. Simons Foundation Autism Research Initiative News and Opinion. Available from: http://sfari.org/news-and-opinion/viewpoint/2011/why-fold-asperger-syndrome-into-autism-spectrum-disorder-in-the-dsm-5
- Harris, G.J., Chabris, C.F., Clark, J., Urban, T., Aharon, I., Steele, S., … & Tager-Flusberg, H. (2006). Brain activation during semantic processing in autism spectrum disorders via functional magnetic resonance imaging. Brain Cogn, 61(1), 54–68.
- Hattier, M.A., Matson, J.L., Tureck, K., & Horovitz, M. (2011). The effects of gender and age on repetitive and/or restricted behaviors and interests in adults with autism spectrum disorders and intellectual disability. Res Dev Disabil, 32(6), 2346–2351.
- Hazlett, H.C., Poe, M.D., Gerig, G., Styner, M., Chappell, C., Smith, R.G., … & Piven, J. (2011). Early brain overgrowth in autism associated with an increase in cortical surface area before age 2 years. Arch Gen Psychiatry, 68(5), 467–476.
- Helzer, J.E., Robins, L.N., McEvoy, L.T., Spitznagel, E.L., Stoltzman, R.K., Farmer, A., & Brockington, L.F. (1985). A comparison of clinical and diagnostic interview schedule diagnoses. Physician reexamination of lay-interviewed cases in the general population. Arch Gen Psychiatry, 42(7), 657–666.
- Hobson, R.P. (2002). The crade of thought: Exploring the origins of thinking. Oxford: Oxford University Press.
- Hughes, V.. (2010). Kevin Pelphrey: Charting the course of the social brain. Simons Foundation Autism Research Initiative News and Opinion. Available from: http://sfari.org/news-and-opinion/investigator-profiles/2010/kevin-pelphrey-charting-the-course-of-the-social-brain [last accessed 16 February 2012].
- Hus, V., Pickles, A., Cook, E.H. Jr, Risi, S., & Lord, C. (2007). Using the autism diagnostic interview--revised to increase phenotypic homogeneity in genetic studies of autism. Biol Psychiatry, 61(4), 438–448.
- Hus, V., Taylor, A., & Lord, C. (2011). Telescoping of caregiver report on the Autism Diagnostic Interview--Revised. J Child Psychol Psychiatry, 52(7), 753–760.
- Hyman, S.E. (2010). The diagnosis of mental disorders: The problem of reification. Annu Rev Clin Psychol, 6, 155–179.
- Insel, T.R., & Cuthbert, B.N. (2009). Endophenotypes: Bridging genomic complexity and disorder heterogeneity. Biol Psychiatry, 66(11), 988–989.
- Jeste, S.S., & Nelson, C.A. 3rd (2009). Event related potentials in the understanding of autism spectrum disorders: An analytical review. J Autism Dev Disord, 39(3), 495–510.
- Jones, W., Carr, K., & Klin, A. (2008). Absence of preferential looking to the eyes of approaching adults predicts level of social disability in 2-year-old toddlers with autism spectrum disorder. Arch Gen Psychiatry, 65(8), 946–954.
- Juranek, J., Filipek, P.A., Berenji, G.R., Modahl, C., Osann, K., & Spence, M.A. (2006). Association between amygdala volume and anxiety level: Magnetic resonance imaging (MRI) study in autistic children. J Child Neurol, 21(12), 1051–1058.
- Kaiser, M.D., Hudac, C.M., Shultz, S., Lee, S.M., Cheung, C., Berken, A.M., … & Pelphrey, K.A. (2010). Neural signatures of autism. Proc Natl Acad Sci USA, 107(49), 21223–21228.
- Kanne, S.M., Gerber, A.J., Quirmbach, L.M., Sparrow, S.S., Cicchetti, D.V., & Saulnier, C.A. (2011). The role of adaptive behavior in autism spectrum disorders: Implications for functional outcome. J Autism Dev Disord, 41(8), 1007–1018.
- Kanner, L. (1943). Autistic disturbances of affective contact. Nervous Child, 250(2), 217–250.
- Keehn, B., Lincoln, A.J., Muller, R.A., & Townsend, J. (2010). Attentional networks in children and adolescents with autism spectrum disorder. J Child Psychol Psychiatry, 51(11), 1251–1259.
- Kim, S.H., & Lord, C. (2010). Restricted and repetitive behaviors in toddlers and preschoolers with autism spectrum disorders based on the Autism Diagnostic Observation Schedule (ADOS). Autism Res, 3(4), 162–173.
- Kim, S.H., & Lord, C. (2012a). Combining information from multiple sources for the diagnosis of autism spectrum disorders for toddlers and young preschoolers from 12 to 47 months of age. J Child Psychol Psychiatry, 53(2), 143–151.
- Kim, S.H., & Lord, C. (2012b). New autism diagnostic interview-revised algorithms for toddlers and young preschoolers from 12 to 47 months of age. J Autism Dev Disord, 42(1), 82–93.
- King, B.H. (1993). Self-injury by people with mental retardation: A compulsive behavior hypothesis. Am J Ment Retard, 98(1), 93–112.
- Kjellmer, L., Hedvall, A., Fernell, E., Gillberg, C., & Norrelgen, F. (2012). Language and communication skills in preschool children with autism spectrum disorders: Contribution of cognition, severity of autism symptoms, and adaptive functioning to the variability. Res Dev Disabil, 33(1), 172–180.
- Kleinhans, N.M., Richards, T., Weaver, K., Johnson, L.C., Greenson, J., Dawson, G., & Aylward, E. (2010). Association between amygdala response to emotional faces and social anxiety in autism spectrum disorders. Neuropsychologia, 48(12), 3665–3670.
- Klin, A., Saulnier, C.A., Sparrow, S.S., Cicchetti, D.V., Volkmar, F.R., & Lord, C. (2007). Social and communication abilities and disabilities in higher functioning individuals with autism spectrum disorders: The Vineland and the ADOS. J Autism Dev Disord, 37(4), 748–759.
- Kraemer, H.C. (2008). DSM Categories and dimensions in clinical and research contexts. In J.E. Helzer, H.C. Kraemer, R.F. Krueger, H.U. Wittchen, P.J. Sirovatka, & D.A. Regier, (Eds), Dimensional approaches in diagnostic classification (pp. 5–17. Arlington: American Psychiatric Association.
- Lam, K.S., Bodfish, J.W., & Piven, J. (2008). Evidence for three subtypes of repetitive behavior in autism that differ in familiality and association with other symptoms. J Child Psychol Psychiatry, 49(11), 1193–1200.
- Lecavalier, L., Aman, M.G., Scahill, L., McDougle, C.J., McCracken, J.T., Vitiello, B., … & Kau, A.S. (2006). Validity of the autism diagnostic interview-revised. Am J Ment Retard, 111(3), 199–215.
- Lee, H., Marvin, A.R., Watson, T., Piggot, J., Law, J.K., Law, P.A., … & Nelson, S.F. (2010). Accuracy of phenotyping of autistic children based on Internet implemented parent report. Am J Med Genet B Neuropsychiatr Genet, 153B(6), 1119–1126.
- Leekam, S.R., Libby, S.J., Wing, L., Gould, J., & Taylor, C. (2002). The diagnostic interview for social and communication disorders: Algorithms for ICD-10 childhood autism and Wing and Gould autistic spectrum disorder. J Child Psychol Psychiatry, 43(3), 327–342.
- Leekam, S., Tandos, J., McConachie, H., Meins, E., Parkinson, K., Wright, C., … & Le Couteur, A. (2007). Repetitive behaviours in typically developing 2-year-olds. J Child Psychol Psychiatry, 48(11), 1131–1138.
- Lord, C., & Bishop, S.L. (2010). Autism spectrum disorders: Diagnosis, prevalence, and services for children and families, Social Policy Report. Society for Research in Child Development, 24(2), 1–21.
- Lord, C., Luyster, R., Guthrie, W., & Pickles, A. (2012). Patterns of developmental trajectories in toddlers with autism spectrum disorders. J Consult Clin Psychol.
- Lord, C., & MaGill-Evans, J. (1995). Peer interactions of autistic children and adolescents. Dev Psychopathol, 7(4), 611–626.
- Lord, C., Petkova, E., Hus, V., Gan, W., Lu, F., Martin, D.M., … & Risi, S. (2012). A Multisite Study of the Clinical Diagnosis of Different Autism Spectrum Disorders. Arch Gen Psychiatry, 69(3), 306–313.
- Lord, C., Risi, S., DiLavore, P.S., Shulman, C., Thurm, A., & Pickles, A. (2006). Autism from 2 to 9 years of age. Arch Gen Psychiatry, 63(6), 694–701.
- Lord, C., Risi, S., Lambrecht, L., Cook, E.H. Jr, Leventhal, B.L., DiLavore, P.C., … & Rutter, M. (2000). The autism diagnostic observation schedule-generic: A standard measure of social and communication deficits associated with the spectrum of autism. J Autism Dev Disord, 30(3), 205–223.
- Lord, C., Rutter, M., & Le Couteur, A. (1999). Autism diagnostic observation schedule (ADOS), manual. Los Angeles: Western Psychological Services.
- Lord, C., Storoschuk, S., Rutter, M., & Pickles, A. (1993). Using the ADI-R to diagnose autism in preschool children. Infant Mental Health Journal, 14(3), 234–252.
- Lotspeich, L.J., Kwon, H., Schumann, C.M., Fryer, S.L., Goodlin-Jones, B.L., Buonocore, M.H., … & Reiss, A.L. (2004). Investigation of neuroanatomical differences between autism and Asperger syndrome. Arch Gen Psychiatry, 61(3), 291–298.
- Luyster, R., Gotham, K., Guthrie, W., Coffing, M., Petrak, R., Pierce, K., … & Lord, C. (2009). The Autism Diagnostic Observation Schedule-toddler module: A new module of a standardized diagnostic measure for autism spectrum disorders. J Autism Dev Disord, 39(9), 1305–1320.
- Luyster, R.J., Kadlec, M.B., Carter, A., & Tager-Flusberg, H. (2008). Language assessment and development in toddlers with autism spectrum disorders. J Autism Dev Disord, 38(8), 1426–1438.
- Magnuson, K.M., & Constantino, J.N. (2011). Characterization of depression in children with autism spectrum disorders. J Dev Behav Pediatr, 32(4), 332–340.
- Malisza, K.L., Clancy, C., Shiloff, D., Foreman, D., Holden, J., Jones, C., … & Chudley, A.E. (2011). Functional evaluation of hidden figures object analysis in children with autistic disorder. J Autism Dev Disord, 41(1), 13–22.
- Mandell, D.S., Wiggins, L.D., Carpenter, L.A., Daniels, J., DiGuiseppi, C., Durkin, M.S., … & Kirby, R.S. (2009). Racial/ethnic disparities in the identification of children with autism spectrum disorders. Am J Public Health, 99(3), 493–498.
- Mandy, W.P., Charman, T., & Skuse, D.H. (2012). Testing the construct validity of proposed criteria for DSM-5 autism spectrum disorder. J Am Acad Child Adolesc Psychiatry, 51(1), 41–50.
- Mattila, M.L., Hurtig, T., Haapsamo, H., Jussila, K., Kuusikko-Gauffin, S., Kielinen, M., … & Moilanen, I. (2010). Comorbid psychiatric disorders associated with Asperger syndrome/high- functioning autism: A community- and clinic-based study. J Autism Dev Disord, 40(9), 1080–1093.
- Mattila, M.L., Kielinen, M., Linna, S.L., Jussila, K., Ebeling, H., Bloigu, R., … & Moilanen, I. (2011). Autism spectrum disorders according to DSM-IV-TR and comparison with DSM-5 draft criteria: An epidemiological study. J Am Acad Child Adolesc Psychiatry, 50(6), 583–592. e511.
- McPartland, J.C., Reichow, B., & Volkmar, F.R. (2012). Sensitivity and specificity of proposed DSM-5 diagnostic criteria for autism spectrum disorder. J Am Acad Child Adolesc Psychiatry.
- Miller, J.N., & Ozonoff, S. (2000). The external validity of Asperger disorder: Lack of evidence from the domain of neuropsychology. J Abnorm Psychol, 109(2), 227–238.
- Mirenda, P., Smith, I.M., Vaillancourt, T., Georgiades, S., Duku, E., Szatmari, P., … & Zwaigenbaum, L. (2010). Validating the Repetitive Behavior Scale-revised in young children with autism spectrum disorder. J Autism Dev Disord, 40(12), 1521–1530.
- Mosconi, M.W., Cody-Hazlett, H., Poe, M.D., Gerig, G., Gimpel-Smith, R., & Piven, J. (2009). Longitudinal study of amygdala volume and joint attention in 2- to 4-year-old children with autism. Arch Gen Psychiatry, 66(5), 509–516.
- Mundy, P., Sigman, M., & Kasari, C. (1990). A longitudinal study of joint attention and language development in autistic children. J Autism Dev Disord, 20(1), 115–128.
- Nelson, C.A. 3rd, & McCleery, J.P. (2008). Use of event-related potentials in the study of typical and atypical development. J Am Acad Child Adolesc Psychiatry, 47(11), 1252–1261.
- Oliver, C., Hall, S., & Murphy, G. (2005). The early development of self-injurious behaviour: Evaluating the role of social reinforcement. J Intellect Disabil Res, 49(Pt 8), 591–599.
- Overton, T., Fielding, C., & de Alba, R.G. (2008). Brief Report: Exploratory analysis of the ADOS revised algorithm: Specificity and predictive value with Hispanic children referred for autism spectrum disorders. J Autism Dev Disord, 38(6), 1166–1169.
- Ozonoff, S., Iosif, A.M., Young, G.S., Hepburn, S., Thompson, M., Colombi, C., … & Rogers, S.J. (2011). Onset patterns in autism: Correspondence between home video and parent report. J Am Acad Child Adolesc Psychiatry, 50(8), 796–806. e791.
- Ozonoff, S., Young, G.S., Carter, A., Messinger, D., Yirmiya, N., Zwaigenbaum, L., & Stone, W.L.. (2011). Recurrence Risk for Autism Spectrum Disorders: A Baby Siblings Research Consortium Study. Pediatrics, 128, e488–e495. Advance online publication; doi:10.1542/peds.2010-2825.
- Pelphrey, K.A., Shultz, S., Hudac, C.M., & Vander Wyk, B.C. (2011). Research review: Constraining heterogeneity: The social brain and its development in autism spectrum disorder. J Child Psychol Psychiatry, 52(6), 631–644.
- Philofsky, A., Hepburn, S.L., Hayes, A., Hagerman, R., & Rogers, S.J. (2004). Linguistic and cognitive functioning and autism symptoms in young children with fragile X syndrome. Am J Ment Retard, 109(3), 208–218.
- Pickett, E., Pullara, O., O’Grady, J., & Gordon, B. (2009). Speech acquisition in older nonverbal individuals with autism: A review of features, methods, and prognosis. Cogn Behav Neurol, 22(1), 1–21.
- Pickles, A., & Angold, A. (2003). Natural categories or fundamental dimensions: On carving nature at the joints and the rearticulation of psychopathology. Dev Psychopathol, 15(3), 529–551.
- Pickles, A., Starr, E., Kazak, S., Bolton, P., Papanikolaou, K., Bailey, A., … & Rutter, M. (2000). Variable expression of the autism broader phenotype: Findings from extended pedigrees. J Child Psychol Psychiatry, 41(4), 491–502.
- Piven, J., Arndt, S., Bailey, J., & Andreasen, N. (1996). Regional brain enlargement in autism: A magnetic resonance imaging study. J Am Acad Child Adolesc Psychiatry, 35(4), 530–536.
- Piven, J., Gayle, J., Landa, R., Wzorek, M., & Folstein, S. (1991). The prevalence of fragile X in a sample of autistic individuals diagnosed using a standardized interview. J Am Acad Child Adolesc Psychiatry, 30(5), 825–830.
- Piven, J., Saliba, K., Bailey, J., & Arndt, S. (1997). An MRI study of autism: The cerebellum revisited. Neurology, 49(2), 546–551.
- Regier, D.A.E., Narrow, W.E.E., Kuhl, E.A.E., & Kupfer, D.J.E. (2011). The conceptual evolution of DSM-5. Washington DC: American Psychiatric Publishing Inc.
- Rice, C. (2009). Prevalence of autism spectrum disorders - autism and developmental disabilities monitoring network, United States, 2006. MMWR Surveillance Summaries, 58(SS10), 1–20.
- Rice, C., Schendel, D., Cunniff, C., & Doernberg, N. (2004). Public health monitoring of developmental disabilities with a focus on the autism spectrum disorders. Am J Med Genet C Semin Med Genet, 125C(1), 22–27.
- Richler, J., Huerta, M., Bishop, S.L., & Lord, C. (2010). Developmental trajectories of restricted and repetitive behaviors and interests in children with autism spectrum disorders. Dev Psychopathol, 22(1), 55–69.
- Risi, S., Lord, C., Gotham, K., Corsello, C., Chrysler, C., Szatmari, P., … & Pickles, A. (2006). Combining information from multiple sources in the diagnosis of autism spectrum disorders. J Am Acad Child Adolesc Psychiatry, 45(9), 1094–1103.
- Robins, D.L., Fein, D., Barton, M.L., & Green, J.A. (2001). The Modified Checklist for Autism in Toddlers: An initial study investigating the early detection of autism and pervasive developmental disorders. J Autism Dev Disord, 31(2), 131–144.
- Robinson, E.B., Koenen, K.C., McCormick, M.C., Munir, K., Hallett, V., Happe, F., & Ronald, A. (2011). A multivariate twin study of autistic traits in 12-year-olds: Testing the fractionable autism triad hypothesis. Behav Genet, 42, 245–255.
- Ronald, A., Happe, F., Bolton, P., Butcher, L.M., Price, T.S., Wheelwright, S., … & Plomin, R. (2006). Genetic heterogeneity between the three components of the autism spectrum: A twin study. J Am Acad Child Adolesc Psychiatry, 45(6), 691–699.
- Ronald, A., Larsson, H., Anckarsater, H., & Lichtenstein, P. (2011). A twin study of autism symptoms in Sweden. Mol Psychiatry, 16(10), 1039–1047.
- Ruiz Calzada, L., Pistrang, N., & Mandy, W.P. (2012). High-functioning autism and Asperger’s disorder: Utility and meaning for families. J Autism Dev Disord, 42(2), 230–243.
- Rutter, M. (2011). Research review: Child psychiatric diagnosis and classification: Concepts, findings, challenges and potential. J Child Psychol Psychiatry, 52(6), 647–660.
- Rutter, M., Le Couteur, A., & Lord, C. (2003). Autism diagnostic interview-revised-WPS. Los Angeles: Western Psychological Services.
- Rutter, M., LeCouteur, A., & Lord, C. (2003). Autism diagnostic interview-revised (ADI-R) manual. Los Angeles: Western Psychological Services.
- Rutter, M., & Sroufe, L.A. (2000). Developmental psychopathology: Concepts and challenges. Dev Psychopathol, 12(3), 265–296.
- Sanders, S.J., Ercan-Sencicek, A.G., Hus, V., Luo, R., Murtha, M.T., Moreno-De-Luca, D., … & State, M.W. (2011). Multiple recurrent de novo CNVs, including duplications of the 7q11.23 Williams syndrome region, are strongly associated with autism. Neuron, 70(5), 863–885.
- Sanders, J.L., & Morgan, S.B. (1997). Family stress and adjustment as perceived by parents of children and autism or down syndrome: Implications for intervention. Child & Family Behavior Therapy, 19(4), 15–32.
- Schumann, C.M., Barnes, C.C., Lord, C., & Courchesne, E. (2009). Amygdala enlargement in toddlers with autism related to severity of social and communication impairments. Biol Psychiatry, 68(10), 942–949.
- Scott, F.J., Baron-Cohen, S., Bolton, P., & Brayne, C. (2002). The CAST (Childhood Asperger Syndrome Test): Preliminary development of a UK screen for mainstream primary- school-age children. Autism, 6(1), 9–31.
- Scott-Van Zeeland, A.A., Abrahams, B.S., Alvarez-Retuerto, A.I., Sonnenblick, L.I., Rudie, J.D., Ghahremani, D., … & Bookheimer, S.Y. (2010). Altered functional connectivity in frontal lobe circuits is associated with variation in the autism risk gene CNTNAP2. Sci Transl Med, 2(56), 56ra80.
- Sharma, S., Woolfson, L.M., & Hunter, S.C. (2011). Confusion and inconsistency in diagnosis of Asperger syndrome: A review of studies from 1981 to 2010. Autism, doi: 10.1177/1362361311411935.
- Shattuck, P.T., Durkin, M., Maenner, M., Newschaffer, C., Mandell, D.S., Wiggins, L., … & Cuniff, C. (2009). Timing of identification among children with an autism spectrum disorder: Findings from a population-based surveillance study. J Am Acad Child Adolesc Psychiatry, 48(5), 474–483.
- Sheinkopf, S.J., & Siegel, B. (1998). Home-based behavioral treatment of young children with autism. J Autism Dev Disord, 28(1), 15–23.
- Sigman, M., Dijamco, A., Gratier, M., & Rozga, A. (2004). Early detection of core deficits in autism. Ment Retard Dev Disabil Res Rev, 10(4), 221–233.
- Silverman, J.L., Yang, M., Lord, C., & Crawley, J.N. (2010). Behavioural phenotyping assays for mouse models of autism. Nat Rev Neurosci, 11(7), 490–502.
- Skuse, D., Warrington, R., Bishop, D., Chowdhury, U., Lau, J., Mandy, W., & Place, M. (2004). The developmental, dimensional and diagnostic interview (3di): A novel computerized assessment for autism spectrum disorders. J Am Acad Child Adolesc Psychiatry, 43(5), 548–558.
- Smith, V., Mirenda, P., & Zaidman-Zait, A. (2007). Predictors of expressive vocabulary growth in children with autism. J Speech Lang Hear Res, 50(1), 149–160.
- Sparks, B.F., Friedman, S.D., Shaw, D.W., Aylward, E.H., Echelard, D., Artru, A.A., … & Dager, S.R. (2002). Brain structural abnormalities in young children with autism spectrum disorder. Neurology, 59(2), 184–192.
- Stewart, A.J., & Devlin, P.M. (2006). The history of the smallpox vaccine. J Infect, 52(5), 329–334.
- Sukhodolsky, D.G., Scahill, L., Gadow, K.D., Arnold, L.E., Aman, M.G., McDougle, C.J., … & Vitiello, B. (2008). Parent-rated anxiety symptoms in children with pervasive developmental disorders: Frequency and association with core autism symptoms and cognitive functioning. J Abnorm Child Psychol, 36(1), 117–128.
- Susser, E.B., Brown, A., & Matte, T.D. (1999). Prenatal factors and adult mental and physical health. Can J Psychiatry, 44(4), 326–334.
- Swedo, S.E., Cook, E.H., Kaufmann, W.E., Lord, C.E., Rogers, S.J., Wetherby, A., … & Wright, H.H. (2012). Commentary from the DSM-5 Workgroup on Neurodevelopmental Disorders. J Am Acad Child Adolesc Psychiatry.
- Sykes, R. (2001). Penicillin: From discovery to product. Bull World Health Organ, 79(8), 778–779.
- Szatmari, P., Liu, X.Q., Goldberg, J., Zwaigenbaum, L., Paterson, A.D., Woodbury-Smith, M., … & Thompson, A. (2012). Sex differences in repetitive stereotyped behaviors in autism: Implications for genetic liability. Am J Med Genet B Neuropsychiatr Genet, 159B(1), 5–12.
- Tadevosyan-Leyfer, O., Dowd, M., Mankoski, R., Winklosky, B., Putnam, S., McGrath, L., … & Folstein, S.E. (2003). A principal components analysis of the Autism Diagnostic Interview-Revised. J Am Acad Child Adolesc Psychiatry, 42(7), 864–872.
- Vaidya, C.J., Foss-Feig, J., Shook, D., Kaplan, L., Kenworthy, L., & Gaillard, W.D. (2011). Controlling attention to gaze and arrows in childhood: An fMRI study of typical development and Autism Spectrum Disorders. Dev Sci, 14(4), 911–924.
- Veenstra-Vanderweele, J., Christian, S.L., & Cook, E.H.. Jr (2004). Autism as a paradigmatic complex genetic disorder. Annu Rev Genomics Hum Genet, 5, 379–405.
- Venter, A., Lord, C., & Schopler, E. (1992). A follow-up study of high-functioning autistic children. J Child Psychol Psychiatry, 33(3), 489–507.
- Virkud, Y.V., Todd, R.D., Abbacchi, A.M., Zhang, Y., & Constantino, J.N. (2009). Familial aggregation of quantitative autistic traits in multiplex versus simplex autism. Am J Med Genet B Neuropsychiatr Genet, 150B(3), 328–334.
- Volkmar, F.R., & Rutter, M. (1995). Childhood disintegrative disorder: Results of the DSM-IV autism field trial. J Am Acad Child Adolesc Psychiatry, 34(8), 1092–1095.
- Walker, D.R., Thompson, A., Zwaigenbaum, L., Goldberg, J., Bryson, S.E., Mahoney, W.J., … & Szatmari, P. (2004). Specifying PDD-NOS: A comparison of PDD-NOS, Asperger syndrome, and autism. J Am Acad Child Adolesc Psychiatry, 43(2), 172–180.
- Walsh, K.M., & Bracken, M.B. (2011). Copy number variation in the dosage-sensitive 16p11.2 interval accounts for only a small proportion of autism incidence: A systematic review and meta-analysis. Genet Med, 13(5), 377–384.
- Werner, E., Dawson, G., Osterling, J., & Dinno, N. (2000). Brief report: Recognition of autism spectrum disorder before one year of age: A retrospective study based on home videotapes. J Autism Dev Disord, 30(2), 157–162.
- Wetherby, A., & Prizant, B.. (1993). Communication and symbolic behavior scales – Normed edition. Baltimore, MD: Paul H. Brookes.
- Wiggins, L.D., & Robins, D.L. (2008). Brief report: Excluding the ADI-R behavioral domain improves diagnostic agreement in toddlers. J Autism Dev Disord, 38(5), 972–976.
- Wing, L., & Gould, J. (1978). Systematic recording of behaviors and skills of retarded and psychotic children. J Autism Child Schizophr, 8(1), 79–97.
- Wing, L., & Gould, J. (1979). Severe impairments of social interaction and associated abnormalities in children: Epidemiology and classification. J Autism Dev Disord, 9(1), 11–29.
- Wing, L., Gould, J., & Gillberg, C. (2011). Autism spectrum disorders in the DSM-V: Better or worse than the DSM-IV? Res Dev Disabil, 32(2), 768–773.
- World Health Organization (1992). The ICD-10 classification of mental and behavioral disorders: Clinical descriptions and diagnostic guidelines. Geneva, Switzerland: World Health Organization.
- World Health Organization (2012). The International Classification of Diseases 11th Revision. ICD-11 Announcement available from: http://www.who.int/classifications/icd/revision/en/index.html [last accessed 16 January 2012].
- Yerys, B.E., Wallace, G.L., Sokoloff, J.L., Shook, D.A., James, J.D., & Kenworthy, L. (2009). Attention deficit/hyperactivity disorder symptoms moderate cognition and behavior in children with autism spectrum disorders. Autism Res, 2(6), 322–333.
- Zarembo, A.. (2011). Warrior parents fare best in securing autism services. Los Angeles Times. Available from: http://www.latimes.com/news/local/autism/la-me-autism-day-two-html,0,3900437.htmlstory [last accessed 16 February 2012].