Journal of Autism and Developmental Disorders

, Volume 42, Issue 7, pp 1377–1392 | Cite as

Psychometric Study of the Aberrant Behavior Checklist in Fragile X Syndrome and Implications for Targeted Treatment

  • Stephanie M. Sansone
  • Keith F. Widaman
  • Scott S. Hall
  • Allan L. Reiss
  • Amy Lightbody
  • Walter E. Kaufmann
  • Elizabeth Berry-Kravis
  • Ave Lachiewicz
  • Elaine C. Brown
  • David HesslEmail author
Original Paper


Animal studies elucidating the neurobiology of fragile X syndrome (FXS) have led to multiple controlled trials in humans, with the Aberrant Behavior Checklist-Community (ABC-C) commonly adopted as a primary outcome measure. A multi-site collaboration examined the psychometric properties of the ABC-C in 630 individuals (ages 3–25) with FXS using exploratory and confirmatory factor analysis. Results support a six-factor structure, with one factor unchanged (Inappropriate Speech), four modified (Irritability, Hyperactivity, Lethargy/Withdrawal, and Stereotypy), and a new Social Avoidance factor. A comparison with ABC-C data from individuals with general intellectual disability and a list of commonly endorsed items are also reported. Reformulated ABC-C scores based on this FXS-specific factor structure may provide added outcome measure specificity and sensitivity in FXS clinical trials.


FMR1 gene Fragile X syndrome Autism Factor analysis Rating scale Social avoidance 



We are especially grateful for the participants and their families for their contribution to the understanding of fragile X syndrome. We would also like to thank Lisa Cordeiro, Elizabeth Ballinger, Alyssa Chavez, Ava Rezvani, Lia Boyle, Victor Talisa, Nana Asante, Crystal Hervey, and Anna DeSonia for their help with site coordination, data entry and management. This work was supported by NIH K23MH77554 (Hessl), the National Fragile X Foundation (Hessl), FRAXA (Hessl), NIH K08MH081998 (Hall), R01MH050047 (Reiss), and NIH HD24061 (Kaufmann).

Supplementary material

10803_2011_1370_MOESM1_ESM.pdf (103 kb)
Supplementary material 1 (PDF 104 kb)


  1. Aman, M. G., Burrow, W. H., & Wolford, P. L. (1995). The Aberrant Behavior Checklist-Community: Factor validity and effect of subject variables for adults in group homes. American Journal of Mental Retardation, 100(3), 283–292.PubMedGoogle Scholar
  2. Aman, M. G., Singh, N. N., Stewart, A. W., & Field, C. J. (1985). The Aberrant Behavior Checklist: A behavior rating scale for the assessment of treatment effects. American Journal of Mental Deficiency, 89(5), 485–491.PubMedGoogle Scholar
  3. Aman, M. G., Smedt, G. D., & Derivan, A. (2002). Double-blind, placebo-controlled study of risperidone for the treatment of disruptive behaviors in children with subaverage intelligence. American Journal of Psychiatry, 14, 1337–1346.CrossRefGoogle Scholar
  4. Arnold, L. E., Vitiello, B., & McDougle, C. (2003). Parent-defined target symptoms respond to risperidone in RUPP autism study: Customer approach to clinical trials. Journal of the American Academy of Child and Adolescent Psychiatry, 42, 1443–1450.PubMedCrossRefGoogle Scholar
  5. Bayley, N. (1993). Manual for the Bayley scales of infant development. New York, NY: Psychological Corporation.Google Scholar
  6. Benjamini, Y., & Hochberg, Y. (1995). Controlling the false discovery rate: A practical and powerful approach to multiple testing. Journal of the Royal Statistical Society, 57(1), 289–300.Google Scholar
  7. Berry-Kravis, E., Hessl, D., Coffey, S., Hervey, C., Schneider, A., Yuhas, J., et al. (2009). A pilot open label, single dose trial of fenobam in adults with fragile X syndrome. Journal of Medical Genetics, 46(4), 266–271. doi: 10.1136/jmg.2008.063701.PubMedCrossRefGoogle Scholar
  8. Berry-Kravis, E., Knox, A., & Hervey, C. (2011). Targeted treatments for fragile X syndrome. Journal of Neurodevelopmental Disorders, 3(3), 193–210. doi:  10.1007/s11689-011-9074-7.PubMedCrossRefGoogle Scholar
  9. Berry-Kravis, E., Krause, S. E., Block, S. S., Guter, S., Wuu, J., Leurgans, S., et al. (2006). Effect of CX516, an AMPA-modulating compound, on cognition and behavior in fragile X syndrome: A controlled trial. Journal of Child and Adolescent Psychopharmacology, 16(5), 525–540. doi: 10.1089/cap.2006.16.525.PubMedCrossRefGoogle Scholar
  10. Berry-Kravis, E., Sumis, A., Hervey, C., Nelson, M., Porges, S. W., Weng, N., et al. (2008). Open-label treatment trial of lithium to target the underlying defect in fragile X syndrome. Journal of Developmental and Behavioral Pediatrics, 29(4), 293–302. doi: 10.1097/DBP.0b013e31817dc447.PubMedCrossRefGoogle Scholar
  11. Bilousova, T. V., Dansie, L., Ngo, M., Aye, J., Charles, J. R., Ethell, D. W., et al. (2009). Minocycline promotes dendritic spine maturation and improves behavioural performance in the fragile X mouse model. Journal of Medical Genetics, 46, 94–102.PubMedCrossRefGoogle Scholar
  12. Brinkley, J., Abramson, R. K., Hall, A., Wright, H. H., Gabriels, R., Gilbert, J. R., et al. (2007). Factor analysis of the aberrant behavior checklist in individuals with autism spectrum disorders. Journal of Autism and Developmental Disorders, 37, 1949–1959.PubMedCrossRefGoogle Scholar
  13. Brown, T. A. (2006). Confirmatory factor analysis for applied research (p. 475). New York, NY: Guilford Press.Google Scholar
  14. Brown, E. C., Aman, M. G., & Havercamp, S. M. (2002). Factor analysis and norms for parent ratings on the Aberrant Behavior Checklist-Community for young people in special education. Research in Developmental Disabilities, 23, 45–60.PubMedCrossRefGoogle Scholar
  15. Browne, M. W., & Cudeck, R. (1992). Alternative ways of assessing model fit. Sociological Methods and Research, 21, 230–258.CrossRefGoogle Scholar
  16. Budimirovic, D. B., Bukelis, I., Cox, C., Gray, R. M., Tierney, E., & Kaufmann, W. E. (2006). Autism spectrum disorder in Fragile X syndrome: Differential contribution of adaptive socialization and social withdrawal. American Journal of Medical Genetics, 140, 1814–1826.Google Scholar
  17. Cattell, R. B. (1961). Theory of situational, instrument, second order, and refraction factors in personality structure research. Psychological Bulletin, 58, 160–174.PubMedCrossRefGoogle Scholar
  18. Cattell, R. B. (1966). The scree test for the number of factors. Multivariate Behavioral Research, 1, 245–276.CrossRefGoogle Scholar
  19. Chou, C. P., Bentler, P. M., & Satorra, A. (1991). Scaled test statistics and robust standard errors for nonormal data in covariance structure analysis: A monte carlo study. British Journal of Mathematical and Statistial Psychology, 44, 347–357.CrossRefGoogle Scholar
  20. Comery, T. A., Harris, J. B., Willems, P. J., Oostra, B. A., Irwin, S. A., Weiler, I. J., et al. (1997). Abnormal dendritic spines in fragile X knockout mice: maturation and pruning deficits. Proceedings of the National Academy of Sciences of the United States of America, 94, 5401–5404.PubMedCrossRefGoogle Scholar
  21. Cordeiro, L., Ballinger, E., Hagerman, R., & Hessl, D. (2010). Clinical assessment of DSM-IV anxiety disorders in fragile X syndrome: Prevalence and characterization. Journal of Neurodevelopmental Disorders, 3, 57–67.PubMedCrossRefGoogle Scholar
  22. Curran, P. J., West, S. G., & Finch, J. F. (1996). The robustness of test statistics to nonnormality and specification error in confirmatory factor analysis. Psychological Methods, 1, 16–29.CrossRefGoogle Scholar
  23. Devys, D., Lutz, Y., Rouyer, N., Bellocq, J. P., & Mandel, J. L. (1993). The FMR-1 protein is cytoplasmic, most abundant in neurons and appears normal in carriers of a fragile X premutation. Nature Genetics, 4(4), 335–340.PubMedCrossRefGoogle Scholar
  24. D’Hulst, C., & Kooy, R. F. (2007). The GABA-A receptor: A novel target for treatment of fragile X? Trends in Neurosciences, 30, 425–431.PubMedCrossRefGoogle Scholar
  25. Dölen, G., & Bear, M. F. (2008). Role for metabotropic glutamate receptor 5 (mGluR5) in the pathogenesis of fragile X syndrome. The Journal of Physiology, 586, 1503–1508.PubMedCrossRefGoogle Scholar
  26. Dykens, E. M., Hodapp, R. M., Ort, S., Finucane, B., Shapiro, L. R., & Leckman, J. F. (1989). The trajectory of cognitive development in males with fragile X syndrome. Journal of the American Academy of Child and Adolescent Psychiatry, 28, 422–426.PubMedCrossRefGoogle Scholar
  27. Eliez, S., Blasey, C. M., Freund, L. S., Hastie, T., & Reiss, A. L. (2001). Brain anatomy, gender and IQ in children and adolescents with fragile X syndrome. Brain: A Journal of Neurology, 124, 1610–1618.CrossRefGoogle Scholar
  28. Elliott, C. (1997). Differential ability scales: Introductory and technical handbook. San Antonio, TX: Psychological Corporation.Google Scholar
  29. Farzin, F., Perry, H., Hessl, D., Loesch, D., Cohen, J., Bacalman, S., et al. (2006). Autism spectrum disorders and attention-deficit/hyperactivity disorder in boys with the fragile X premutation. Journal of Developmental and Behavioral Pediatrics, 27(2), S137–144.PubMedCrossRefGoogle Scholar
  30. Farzin, F., Rivera, S. M., & Hessl, D. (2009). Brief report: Visual processing of faces in individuals with fragile X syndrome: An eye tracking study. Journal of Autism and Developmental Disorders, 39(6), 946–952. doi: 10.1007/s10803-009-0744-1.PubMedCrossRefGoogle Scholar
  31. Farzin, F., Scaggs, F., Hervey, C., Berry-Kravis, E., & Hessl, D. (2011). Reliability of eye tracking and pupillometry measures in individuals with fragile X syndrome. Journal of Autism and Developmental Disorders. doi:  10.1007/s10803-011-1176-2.
  32. Ferrier, L. J., Bashir, A. S., Meryash, D. L., Johnston, J., & Wolff, P. (1991). Conversational skills of individuals with fragile X syndrome: A comparison with autism and Down syndrome. Developmental Medicine and Child Neurology, 33(9), 776–788. doi: 10.1111/j.1469-8749.1991.tb14961.x.PubMedCrossRefGoogle Scholar
  33. Floyd, F. J., & Widaman, K. F. (1995). Factor analysis in the development and refinement of clinical assessment instruments. Psychological Assessment, 7(3), 286–299. doi: 10.1037//1040-3590.7.3.286.CrossRefGoogle Scholar
  34. Freund, L. S., & Reiss, A. L. (1991). Rating problem behaviors in outpatients with mental retardation: Use of the aberrant behavior checklist. Research in Developmental Disabilities, 12(4), 435–451.PubMedCrossRefGoogle Scholar
  35. Galvez, R., & Greenough, W. T. (2005). Sequence of abnormal dendritic spine development in primary somatosensory cortex of a mouse model of the fragile X mental retardation syndrome. American Journal of Medical Genetics, 135(2), 155–160. doi: 10.1002/ajmg.a.30709.PubMedGoogle Scholar
  36. Garrett, A. S., Menon, V., MacKenzie, K., & Reiss, A. L. (2004). Here’s looking at you, kid: Neural systems underlying face and gaze processing in fragile X syndrome. Archives of General Psychiatry, 61(3), 281–288. doi: 10.1001/archpsyc.61.3.281.PubMedCrossRefGoogle Scholar
  37. Giedd, J. N. (2004). Structural magnetic resonance imaging of the adolescent brain. Annals of the New York Academy of Sciences, 1021, 77–85.PubMedCrossRefGoogle Scholar
  38. Giedd, J. N., Blumenthal, J., Jeffries, N. O., Castellanos, F. X., Liu, H., Zijdenbos, A., et al. (1999). Brain development during childhood and adolescence: A longitudinal MRI study. Nature Neuroscience, 2(10), 861–863. doi: 10.1038/13158.PubMedCrossRefGoogle Scholar
  39. Hagerman, P. J. (2008). The fragile X prevalence paradox. Journal of Medical Genetics, 45(8), 498–499. doi: 10.1136/jmg.2008.059055.PubMedCrossRefGoogle Scholar
  40. Hagerman, R. J., Hull, C. E., Safanda, J. F., Carpenter, I., Staley, L. W., O’Connor, R. A., et al. (1994). High functioning fragile X males: Demonstration of an unmethylated fully expanded FMR-1 mutation associated with protein expression. American Journal of Medical Genetics, 51(4), 298–308. doi: 10.1002/ajmg.1320510404.PubMedCrossRefGoogle Scholar
  41. Hall, S. S., Debernardis, M., & Reiss, A. L. (2006). Social escape behaviors in children with fragile X syndrome. Journal of Autism and Developmental Disorders, 36(7), 935–947. doi:  10.1007/s10803-006-0132-z.PubMedCrossRefGoogle Scholar
  42. Hall, S. S., Lightbody, A., & Reiss, A. L. (2008). Compulsive, self-injurious, and autistic behavior in children and adolescents with fragile X syndrome. American Journal of Mental Retardation, 113(1), 44–53. doi: 10.1352/0895-8017.PubMedCrossRefGoogle Scholar
  43. Hassiotis, A., Robotham, D., Canagasabey, A., Romeo, R., Langridge, D., Blizard, R., et al. (2009). Randomized, single-blind, controlled trial of a specialist behavior therapy team for challenging behavior in adults with intellectual disabilities. The American Journal of Psychiatry, 166, 1278–1285. doi: 10.1176/appi.ajp.2009.08111747.PubMedCrossRefGoogle Scholar
  44. Hau, K. T., & Marsh, H. W. (2004). The use of item parcels in structural equation modeling: Non-normal data and small sample sizes. The British Journal of Mathematical and Statistical Psychology, 57, 327–351.PubMedCrossRefGoogle Scholar
  45. Hessl, D., Glaser, B., Dyer-Friedman, J., & Reiss, A. L. (2006). Social behavior and cortisol reactivity in children with fragile X syndrome. Journal of Child Psychology and Psychiatry, 47(6), 602–610. doi: 10.1111/j.1469-7610.2005.01556.x.PubMedCrossRefGoogle Scholar
  46. Hessl, D., Tassone, F., Cordeiro, L., Koldewyn, K., McCormick, C., Green, C., et al. (2008). Brief report: aggression and stereotypic behavior in males with fragile X syndrome—moderating secondary genes in a “single gene” disorder. Journal of Autism and Developmental Disorders, 38(1), 184–189. doi: 10.1007/s10803-007-0365-5.PubMedCrossRefGoogle Scholar
  47. Hodapp, R. M., Dykens, E. M., Hagerman, R. J., Schreiner, R., Lachiewicz, A. M., & Leckman, J. F. (1990). Developmental implications of changing trajectories of IQ in males with fragile X syndrome. Journal of the American Academy of Child and Adolescent Psychiatry, 29(2), 214–219. doi: 10.1097/00004583-199003000-00009.PubMedCrossRefGoogle Scholar
  48. Hu, L., & Bentler, P. M. (1999). Cutoff criteria for fit indexes in covariance structure analysis: Conventional criteria versus new alternatives. Structural Equation Modeling: A Multidisciplinary Journal, 6(1), 1–55.CrossRefGoogle Scholar
  49. Humphreys, L. G., & Montanelli, R. G. (1975). An investigation of the parallel analysis criterion for determining the number of common factors. Multivariate Behavioral Research, 10(2), 193–205. doi: 10.1207/s15327906mbr1002_5.CrossRefGoogle Scholar
  50. Irwin, S. A., Galvez, R., & Greenough, W. T. (2000). Dendritic spine structural anomalies in fragile-X mental retardation syndrome. Cerebral Cortex, 10(10), 1038–1044.PubMedCrossRefGoogle Scholar
  51. Irwin, S. A., Idupulapati, M., Gilbert, M. E., Harris, J. B., Chakravarti, A. B., Rogers, E. J., et al. (2002). Dendritic spine and dendritic field characteristics of layer V pyramidal neurons in the visual cortex of fragile-X knockout mice. American Journal of Medical Genetics, 111(2), 140–146. doi: 10.1002/ajmg.10500.PubMedCrossRefGoogle Scholar
  52. Irwin, S. A., Patel, B., Idupulapati, M., Harris, J. B., Crisostomo, R. A., Larsen, B. P., et al. (2001). Abnormal dendritic spine characteristics in the temporal and visual cortices of patients with fragile-X syndrome: A quantitative examination. American Journal of Medical Genetics, 98(2), 161–167.PubMedCrossRefGoogle Scholar
  53. Jacquemont, S., Curie, A., des Portes, V., Torrioli, M. G., Berry-Kravis, E., & Hagerman, R. J., et al. (2011). Epigenetic modification of the FMR1 gene in fragile X syndrome is associated with differential response to the mGluR5 antagonist AFQ056. Science Translational Medicine, 3(64), 64ra1. doi:  10.1126/scitranslmed.3001708.
  54. Jin, P., & Warren, S. T. (2003). New insights into fragile X syndrome: From molecules to neurobehaviors. Trends in Biochemical Sciences, 28(3), 152–158.PubMedCrossRefGoogle Scholar
  55. Kau, A. S. M., Tierney, E., Bukelis, I., Stump, M. H., Kates, W. R., Trescher, W. H., et al. (2004). Social behavior profile in young males with fragile X syndrome: Characteristics and specificity. American Journal of Medical Genetics, 126A(1), 9–17. doi: 10.1002/ajmg.a.20218.PubMedCrossRefGoogle Scholar
  56. Kaufman, A. (1983). K-ABC: Kaufman assessment battery for children: Interpretive manual. NewYork, NY: Psychological Corporation.Google Scholar
  57. Kaufmann, W. E., Cortell, R., Kau, A. S. M., Bukelis, I., Tierney, E., Gray, R. M., et al. (2004). Autism spectrum disorder in fragile X syndrome: Communication, social interaction, and specific behaviors. American Journal of Medical Genetics, 129A(3), 225–234. doi: 10.1002/ajmg.a.30229.PubMedCrossRefGoogle Scholar
  58. Kesler, S. R., Lightbody, A. A., Reiss, A. L. (2009). Cholinergic dysfunction in fragile X syndrome and potential intervention: A preliminary 1H MRS study. American Journal of Medical Genetics, 149A(3), 403–407.PubMedCrossRefGoogle Scholar
  59. King, B., & Wright, D. (2001). Double-blind, placebo-controlled study of amantadine hydrochloride in the treatment of children with autistic disorder. Journal of the American Academy of Child and Adolescent Psychiatry, 40(6), 658–665.PubMedCrossRefGoogle Scholar
  60. Kishton, J. M., & Widaman, K. F. (1994). Unidimensional versus domain representative parceling of questionnaire items: An empirical example. Educational and Psychological Measurement, 54(3), 757–765. doi: 10.1177/0013164494054003022.CrossRefGoogle Scholar
  61. Lachiewicz, A. M., & Dawson, D. V. (2005). Behavior problems of young girls with fragile X syndrome: Factor scores on the Conners’ parent’s questionnaire. American Journal of Medical Genetics, 51(4), 364–369.CrossRefGoogle Scholar
  62. Little, T., Cunningham, W., Shahar, G., & Widaman, K. F. (2002). To parcel or not to parcel: Exploring the question, weighing the merits. Structural Equation Modeling: A Multidisciplinary Journal, 9(2), 151–173. doi: 10.1207/S15328007SEM0902_1.CrossRefGoogle Scholar
  63. Mardia, K. V. (1970). Measures of multivariate skewness and kurtosis with applications. Biometrika, 57(3), 519–530. doi: 10.1093/biomet/57.3.519.CrossRefGoogle Scholar
  64. Marshburn, E. C., & Aman, M. G. (1992). Factor validity and norms for the Aberrant Behavior Checklist in a community sample of children with mental retardation. Journal of Autism and Developmental Disorders, 22(3), 357–373.PubMedCrossRefGoogle Scholar
  65. McCarthy, D. (1972). Manual for the McCarthy scales of children’s abilities. New York: Psychological Corporation.Google Scholar
  66. McCracken, J. T., McGough, J., Shah, B., Cronin, P., Hong, D., Aman, M. G., et al. (2002). Risperidone in children with autism and serious behavioral problems. New England Journal of Medicine, 347(5), 314–321.PubMedCrossRefGoogle Scholar
  67. Menon, V., Leroux, J., White, C. D., & Reiss, A. L. (2004). Frontostriatal deficits in fragile X syndrome: Relation to FMR1 gene expression. Proceedings of the National Academy of Sciences of the United States of America, 101(10), 3615–3620. doi: 10.1073/pnas.0304544101.PubMedCrossRefGoogle Scholar
  68. Mullen, E. (1995). Mullen scales of early learning. Circle Pines, MN: American Guidance Service.Google Scholar
  69. Munir, F., Cornish, K. M., & Wilding, J. (2000). A neuropsychological profile of attention deficits in young males with fragile X syndrome. Neuropsychologia, 38(9), 1261–1270.PubMedCrossRefGoogle Scholar
  70. Nevitt, J., & Hancock, G. R. (2004). Evaluating small sample approaches for model test statistics in structural equation modeling. Multivariate Behavioral Research, 39(3), 439–478.CrossRefGoogle Scholar
  71. Newton, J. T., & Sturmey, P. (1988). The Aberrant Behaviour Checklist: A British replication and extension of its psychometric properties. Journal of Mental Deficiency Research, 32, 87–92.PubMedGoogle Scholar
  72. Norris, M., & Lecavalier, L. (2010). Evaluating the use of exploratory factor analysis in developmental disability psychological research. Journal of Autism and Developmental Disorders, 40(1), 8–20. doi: 10.1007/s10803-009-0816-2.PubMedCrossRefGoogle Scholar
  73. Ono, Y. (1996). Factor validity and reliability for the Aberrant Behavior Checklist-Community in a Japanese population with mental retardation. Science, 17(4), 303–309.Google Scholar
  74. Paribello, C., Tao, L., Folino, A., Berry-Kravis, E., Tranfaglia, M., & Ethell, I. M, et al. (2010). Open-label add-on treatment trial of minocycline in fragile X syndrome. BMC Neurology, 10(1), 91. doi: 10.1186/1471-2377-10-91.
  75. Pearson, D., & Santos, C. (2003). Treatment effects of methylphenidate on behavioral adjustment in children with mental retardation and ADHD. Journal of the American Academy of Child and Adolescent Psychiatry, 42(2), 209–216.PubMedCrossRefGoogle Scholar
  76. Roid, G., & Miller, L. J. (1997). Leiter international performance scale-revised: Examiner’s manual. Wood Dale, IL: Stoelting Co.Google Scholar
  77. Roid, G. (2003). Stanford-Binet intelligence scales (5th ed.). Itasca, IL: Riverside Publishers.Google Scholar
  78. Rojahn, J., Aman, M. G., Matson, J. L., & Mayville, E. (2003). The aberrant behavior checklist and the behavior problems inventory: Convergent and divergent validity. Research in Developmental Disabilities, 24, 391–404. Elsevier. doi: 10.1016/S0891-4222(03)00055-6.
  79. Rosseel, Y. (2010). lavaan: An R package for structural equation modeling and more Version 0. 3-1. Word Journal of The International Linguistic Association, 1, 1–32.Google Scholar
  80. Satorra, A., & Bentler, P. (1994). Corrections to test statistics and standard errors in covariance structure analysis. In A. von Eye & C. C. Clogg (Eds.), Latent variables analysis: Applications for developmental research (pp. 399–419). Thousand Oaks, CA: Sage.Google Scholar
  81. Schwarz, G. (1978). Estimating the dimension of a model. The Annals of Statistics, 6(2), 461–464.CrossRefGoogle Scholar
  82. Shea, S., Turgay, A., Carroll, A., & Schulz, M. (2004). Risperidone in the treatment of disruptive behavioral symptoms in children with autistic and other pervasive developmental disorders. Pediatrics, 14(5), 634–641.CrossRefGoogle Scholar
  83. Steiger, J., & Lind, J. (1980). Statistically based tests for the number of common factors. In Annual meeting of the Psychometric Society.Google Scholar
  84. Sudhalter, V., & Belser, R. C. (2001). Conversational characteristics of children with fragile X syndrome: Tangential language. American Journal on Mental Retardation, 106(5), 389–400.PubMedCrossRefGoogle Scholar
  85. Sudhalter, V., Cohen, I. L., Silverman, W., & Wolf-Schein, E. G. (1990). Conversational analyses of males with fragile X, Down syndrome, and autism: Comparison of the emergence of deviant language. American Journal on Mental Retardation, 94(4), 431–441.PubMedGoogle Scholar
  86. Sullivan, K., Hatton, D., Hammer, J., Sideris, J., Hooper, S., Ornstein, P., et al. (2006). ADHD symptoms in children with FXS. American Journal of Medical Genetics, 140A(21), 2275–2288. doi: 10.1002/ajmg.a.CrossRefGoogle Scholar
  87. Symons, F. J., Clark, R. D., Hatton, D. D., Skinner, M., & Bailey, D. B. (2003). Self-injurious behavior in young boys with fragile X syndrome. American Journal of Medical Genetics, 118A(2), 115–121. doi: 10.1002/ajmg.a.10078.PubMedCrossRefGoogle Scholar
  88. R Development Core Team (2010). R: A language and environment for statistical computing—reference index. R Foundation for Statisical Computing. Retrieved from
  89. Tucker, L. R., & Lewis, C. (1973). A reliability coefficient for maximum likelihood factor analysis. Psychometrika, 38(1), 1–10.CrossRefGoogle Scholar
  90. Van Bellinghen, M., & De Troch, C. (2001). Risperidone in the treatment of behavioral disturbances in children and adolescents with borderline intellectual functioning: A double-blind, placebo-controlled pilot trial. Journal of Child and Adolescent Psychopharmacology, 11(1), 5–13. doi: 10.1089/104454601750143348.PubMedCrossRefGoogle Scholar
  91. Wang, L., & Hagerman, R. (2010). Arbaclofen treatment is associated with global behavioral improvement in fragile X syndrome (FXS): Results of a randomized, controlled phase 2 trial. In Proceedings from the 2010 annual meeting of the Society for Developmental and Behavioral Pediatrics. Phoenix, AZ.Google Scholar
  92. Watson, C., Hoeft, F., Garrett, A. S., Hall, S. S., & Reiss, A. L. (2008). Aberrant brain activation during gaze processing in boys with fragile X syndrome. Archives of General Psychiatry, 65(11), 1315–1323. doi: 10.1001/archpsyc.65.11.1315.PubMedCrossRefGoogle Scholar
  93. Wechsler, D. (1997). Wechsler adult intelligence scale-III (WAIS-III). San Antonio, TX: The Psychological Corporation.Google Scholar
  94. Wechsler, D. (1999). Manual for the Wechsler abbreviated intelligence scale (WASI). San Antonio, TX: The Psychological Corporation.Google Scholar
  95. Wechsler, D. (2003). Wechsler intelligence scale for children-fourth edition (WISC-IV). San Antonio, TX: The Psychological Corporation.Google Scholar
  96. Wechsler, D. (2006a). WPPSI-R, manual: Wechsler preschool and primary scale of intelligence-revised. San Antonio: Psychological Corporation.Google Scholar
  97. Wechsler, D. (2006b). Wechsler nonverbal scale of ability. New York, NY: The Psychological Corporation.Google Scholar
  98. Zinbarg, R. E., Revelle, W., Yovel, I., & Li, W. (2005). Cronbach’s α, Revelle’s β, and Mcdonald’s ωH: Their relations with each other and two alternative conceptualizations of reliability. Psychometrika, 70(1), 123–133. doi: 10.1007/s11336-003-0974-7.CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • Stephanie M. Sansone
    • 1
  • Keith F. Widaman
    • 2
  • Scott S. Hall
    • 3
  • Allan L. Reiss
    • 3
  • Amy Lightbody
    • 3
  • Walter E. Kaufmann
    • 4
  • Elizabeth Berry-Kravis
    • 5
  • Ave Lachiewicz
    • 6
    • 7
  • Elaine C. Brown
    • 7
  • David Hessl
    • 1
    • 8
    Email author
  1. 1.Medical Investigation of Neurodevelopmental Disorders (MIND) InstituteUniversity of California Davis Medical CenterSacramentoUSA
  2. 2.Department of PsychologyUniversity of California, DavisDavisUSA
  3. 3.Department of Psychiatry and Behavioral Sciences, Center for Interdisciplinary Brain Sciences ResearchStanford UniversityStanfordUSA
  4. 4.Center for Genetic Disorders of Cognition and Behavior, Kennedy Krieger InstituteJohns Hopkins University School of MedicineBaltimoreUSA
  5. 5.Departments of Pediatrics, Neurological Sciences, BiochemistryRush University Medical CenterChicagoUSA
  6. 6.Departments of Pediatrics and Psychiatry and Behavioral SciencesDuke University Medical CenterDurhamUSA
  7. 7.Private PracticeRenoUSA
  8. 8.Department of Psychiatry and Behavioral SciencesUniversity of California, Davis, School of MedicineSacramentoUSA

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