Defining Autism Subgroups: A Taxometric Solution

  • David G. Ingram
  • T. Nicole Takahashi
  • Judith H. MilesEmail author
Original Paper


The purpose of the present study was to determine which behavioral and physical phenotypes would be most likely to divide the ASD population into discrete subgroups. The taxometric methods of Maximum Covariance (MAXCOV) and Minus Mean Below A Cut (MAMBAC) were employed to test for categorical versus continuous variation of each phenotype across the ASD population. Data was retrieved from the Autism Genetic Resource Exchange and the University of Missouri Autism Database. The results of our analyses support subgrouping subjects based on variation in social interaction/communication, intelligence, and essential/complex phenotype; in contrast, subjects varied continuously in insistence on sameness, repetitive sensory motor actions, language acquisition, and, tentatively, adaptive functioning. Stratifying ASD samples based on taxometric results should increase power in gene-finding studies and aid in treatment efficacy research.


Autism subgroups Taxometrics 



We gratefully acknowledge the resources provided by the Autism Genetic Resource Exchange (AGRE) Consortium and the participating AGRE families. The Autism Genetic Resource Exchange is a program of Cure Autism Now and is supported, in part, by grant MH64547 from the National Institute of Mental Health to Daniel H. Geschwind (PI). We would like to thank John Ruscio for his help with taxometric theory, Thomas Piasecki for introducing us to taxometrics, and finally our patients, whose courage makes this work possible. We received support from the Missouri Department of Mental Health, Leda J. Sears Trust, and Ridgeway Scholarship.


  1. AGRE (n.d.). AGRE affected status categories. Retrieved 30 July 2007, from
  2. American Psychiatric Association. (2000). Diagnostic and statistical manual of mental disorders (4th ed.). Text revised ed. Washington, DC.Google Scholar
  3. Beglinger, L. J., & Smith, T. H. (2001). A review of subtyping in autism and proposed dimensional classification model. Journal of Autism and Developmental Disorders, 31(4), 411–422.PubMedCrossRefGoogle Scholar
  4. Blanchard, J. J., Horan, W. P., & Collins, L. M. (2005). Examining the latent structure of negative symptoms: Is there a distinct subtype of negative symptom schizophrenia? Schizophrenia Research, 77(2–3), 151–165.PubMedCrossRefGoogle Scholar
  5. Bolte, S., & Poustka, F., (2002). The relation between general cognitive level and adaptive behavior domains in individuals with autism with and without co-morbid mental retardation. Child Psychiatry and Human Development, 33(2), 165–172.PubMedCrossRefGoogle Scholar
  6. Bolton, P., et al. (1994). A case-control family history study of autism. Journal of Child Psychology and Psychiatry, 35(5), 877–900.PubMedCrossRefGoogle Scholar
  7. Bradford, Y., et al. (2001). Incorporating language phenotypes strengthens evidence of linkage to autism. American Journal of Medical Genetics, 105(8), 539–547.PubMedCrossRefGoogle Scholar
  8. Buxbaum, J. D., et al. (2001). Evidence for a susceptibility gene for autism on chromosome 2 and for genetic heterogeneity. American Journal of Human Genetics, 68(6), 1514–1520.PubMedCrossRefGoogle Scholar
  9. Cole, D. A. (2004). Taxometrics in psychopathology research: An introduction to some of the procedures and related methodological issues. Journal of Abnormal Psychology, 113(1), 3–9.PubMedCrossRefGoogle Scholar
  10. Constantino, J. N., & Todd, R. D. (2003). Autistic traits in the general population: A twin study. Archives of General Psychiatry, 60(5), 524–530.PubMedCrossRefGoogle Scholar
  11. Cuccaro, M. L., et al. (2003). Factor analysis of restricted and repetitive behaviors in autism using the Autism Diagnostic Interview-R. Child Psychiatry and Human Development, 34(1), 3–17.PubMedCrossRefGoogle Scholar
  12. Georgiades, S., et al. (2007). Structure of the autism symptom phenotype: A proposed multidimensional model. Journal of the Amercian Academy of Child and Adolescent Psychiatry, 46(2), 188–196.CrossRefGoogle Scholar
  13. Haslam, N. (2003). Categorical versus dimensional models of mental disorder: The taxometric evidence. The Australin and New Zealand Journal of Psychiatry, 37(6), 696–704.CrossRefGoogle Scholar
  14. Haslam, N., & Beck, A. T. (1994). Subtyping major depression: A taxometric analysis. Journal of Abnormal Psychoogy, 103(4), 686–692.CrossRefGoogle Scholar
  15. Hus, V., et al. (2007). Using the autism diagnostic interview—Revised to increase phenotypic homogeneity in genetic studies of autism. Biological Psychiatry, 61(4), 438–448.PubMedCrossRefGoogle Scholar
  16. Klin, A., et al. (2007). Social and communication abilities and disabilities in higher functioning individuals with autism spectrum disorders: The Vineland and the ADOS. Journal of Autism and Developmental Disorders, 37(4), 748–759.PubMedCrossRefGoogle Scholar
  17. Lecavalier, L., et al. (2006). Validity of the autism diagnostic interview-revised. American Journal of Mental Retardation, 111(3), 199–215.PubMedCrossRefGoogle Scholar
  18. Meehl, P. E. (1995). Bootstraps taxometrics. Solving the classification problem in psychopathology. The Amercian Psychologist, 50(4), 266–275.CrossRefGoogle Scholar
  19. Miles, J. H., & Hillman, R. E. (2000). Value of a clinical morphology examination in autism. American Journal of Medical Genetics, 91(4), 245–253.PubMedCrossRefGoogle Scholar
  20. Miles, J. H., et al. (2000). Head circumference is an independent clinical finding associated with autism. American Journal of Medical Genetics, 95, 339–350.PubMedCrossRefGoogle Scholar
  21. Miles, J. H., et al. (2005). Essential versus complex autism: Definition of fundamental prognostic subtypes. American Journal of Medical Genetics A, 135(2), 171–180.CrossRefGoogle Scholar
  22. Muhle, R., Trentacoste, S. V., & Rapin, I. (2004). The genetics of autism. Pediatrics, 113(5), e472–e486.PubMedCrossRefGoogle Scholar
  23. Pearson Assessments. (n.d.). PPVT-III:peabody picture vocabulary test-third edition. Retrieved 30 July 2007, from
  24. Pickles, A., et al. (2000). Variable expression of the autism broader phenotype: Findings from extended pedigrees. Journal of Child Psychology and Psychiatry, 41(4), 491–502.PubMedCrossRefGoogle Scholar
  25. Raven, J., Raven, J. C., & Court, J. H. (1998). Manual for Raven’s progressive matrices and vocabulary scales. San Antonio: Harcourt Assessment.Google Scholar
  26. Ruscio, J., Haslam, N., & Ruscio, A. M. (2006). Introduction to the taxometric method (1st ed.). Mahwah, NJ: Lawrence Erlbaum Associates.Google Scholar
  27. Ruscio, J., & Ruscio, A. M. (2004). Clarifying boundary issues in psychopathology: The role of taxometrics in a comprehensive program of structural research. Journal of Abnormal Psychology, 113(1), 24–38.PubMedCrossRefGoogle Scholar
  28. Saulnier, C. A., & Klin, A. (2007). Brief report: Social and communication abilities and disabilities in higher functioning individuals with autism and asperger syndrome. Journal of Autism and Developmental Disorders, 37(4), 788–793.PubMedCrossRefGoogle Scholar
  29. Shao, Y., et al. (2003). Fine mapping of autistic disorder to chromosome 15q11-q13 by use of phenotypic subtypes. American Journal of Human Genetics, 72(3), 539–548.PubMedCrossRefGoogle Scholar
  30. Shao, Y., et al. (2002). Phenotypic homogeneity provides increased support for linkage on chromosome 2 in autistic disorder. American Journal of Human Genetics, 70(4), 1058–1061.PubMedCrossRefGoogle Scholar
  31. Szatmari, P., et al. (2006). Investigating the structure of the restricted, repetitive behaviours and interests domain of autism. Journal of Child Psychology and Psychiatry, 47(6), 582–590.PubMedCrossRefGoogle Scholar
  32. van Lang, N. D., et al. (2006). Structural equation analysis of a hypothesised symptom model in the autism spectrum. Journal of Child Psychology and Psychiatry, 47(1), 37–44.PubMedCrossRefGoogle Scholar
  33. Waelde, L. C., Silvern, L., & Fairbank, J. A. (2005). A taxometric investigation of dissociation in Vietnam veterans. Journal of Traumatic Stress, 18(4), 359–369.PubMedCrossRefGoogle Scholar
  34. Williamson, D. A., Gleaves, D. H., & Stewart, T. M. (2005). Categorical versus dimensional models of eating disorders: An examination of the evidence. The International Journal of Eating Disorders, 37(1), 1–10.PubMedCrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2007

Authors and Affiliations

  • David G. Ingram
    • 1
  • T. Nicole Takahashi
    • 1
  • Judith H. Miles
    • 1
    Email author
  1. 1.Thompson Center for Autism & Neurodevelopmental DisordersUniversity of Missouri-ColumbiaColumbiaUSA

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