Specifying PDD-NOS: A Comparison of PDD-NOS, Asperger Syndrome, and Autism
Abstract
Objective To describe the clinical characteristics of children given a diagnosis of pervasive developmental disorder-not otherwise specified (PDD-NOS) by expert clinicians and to compare these to the clinical characteristics of children given a diagnosis of autism and Asperger syndrome (AS). Method Two hundred sixteen children with autism, 33 with AS, and 21 with PDD-NOS were compared on measures of level of functioning (communication, daily living and social skills, IQ, and age of acquisition of language) and on various symptoms of autism (impaired communication and reciprocal social interaction and a preference for repetitive and stereotyped activities). Results In terms of level of functioning measures, the PDD-NOS children had scores that were between those of the children with autism and those of the children with AS. In contrast, the PDD-NOS group had fewer autistic symptoms, especially repetitive stereotyped behaviors, than both the autism and AS groups (chi2 = 11.06, p =.004). Children with PDD-NOS could be placed into one of three subgroups: a high-functioning group (24%) who resembled AS but had transient language delay or mild cognitive impairment; a subgroup resembling autism (24%) but who had late age of onset or too severe cognitive delays or were too young to potentially meet the full diagnostic criteria for autism; and a group (52%) not fulfilling the criteria for autism because of fewer stereotyped and repetitive behaviors. Conclusions With some revision to current diagnostic criteria, a more homogenous atypical group with significant impairments in social-communication but fewer repetitive behaviors can be differentiated from the more nonspecific PDD-NOS group. This differentiation may lead to better reliability in diagnosis and to further progress in studies of etiology.
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Efforts to categorize the heterogeneity in ASDs have been largely unsuccessful because distinct, empirically defined subgroups have yet to be reliably identified.
“This effort has been largely unsuccessful because distinct, empirically defined subgroups have yet to be reliably identified.”
From DSM-5 and autism spectrum disorders (ASDs): an opportunity for identifying ASD subtypes (2013) · cites this paper as [9]
Before DSM-5, diagnostic criteria had limited reliability in assigning subcategory diagnosis.
“Before DSM-5, there were poor diagnostic criteria with limited reliability in assigning subcategory diagnosis (Walker et al. 2004).”
From Autism Spectrum Disorder and auditory sensory alterations: a systematic review on the integrity of cognitive and neuronal functions related to auditory processing (2023) · cites this paper as Walker et al. 2004
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Association testing of copy number variants in schizophrenia and autism spectrum disorders
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“fit to the criteria for restricted interests and repetitive behavior [89], which is also the ASD criterion least likely to be represented in premorbidity to schizophrenia.”
BackgroundKleinhans, N. M., Schweinsburg, B. C., Cohen, D. N., Müller, R.-A., & Courchesne, E. (2007) · Brain Research · doi:10.1016/j.brainres.2007.04.081 · Cited by 59 · see citing works
Brukner-Wertman, Y., Laor, N., & Golan, O. (2016) · Journal of Autism and Developmental Disorders · doi:10.1007/s10803-016-2814-5 · Cited by 61 · see citing works
“Researchers highlighted the limitations of these undifferentiated diagnostic categories (Towbin 2005; Walker et al. 2004; Mandy et al. 2011), stressing the need to improve the definition of partial states of autism.”
BackgroundHarrop, C. (2014) · Autism · doi:10.1177/1362361314545685 · Cited by 58 · see citing works
“, 2006) and vast heterogeneity (Harrop et al., 2014; Walker et al., 2004) further complicate the ability to make recommendations for intervention.”
BackgroundDolev, S., Oppenheim, D., Koren‐Karie, N., & Yirmiya, N. (2009) · Parenting · doi:10.1080/15295190902844332 · Cited by 56 · see citing works
“As is commonly found (eg, Walker et al, 2004 ), children's diagnosis was associated with their functioning, with children with PDD-NOS more likely to be high functioning and children with AD more likely to be low functioning ( likelihood ratio = 6.”
MethodVisser, J. C., Rommelse, N., Vink, L., Schrieken, M., Oosterling, I. J., van der Gaag, R. J., & Buitelaar, J. K. (2013) · Journal of Autism and Developmental Disorders · doi:10.1007/s10803-012-1678-6 · Cited by 50 · see citing works
“PDD-NOS is mostly criticized for its heterogeneity, since the criteria can also be met when all three domains are affected but less severely (Towbin et al. 2005; Walker et al. 2004).”
BackgroundConfusion and inconsistency in diagnosis of Asperger syndrome: a review of studies from 1981 to 2010
Sharma, S., Woolfson, L. M., & Hunter, S. C. (2012) · Autism · doi:10.1177/1362361311411935 · Cited by 47 · see citing works
“No difference on current social functioning Walker et al. (2004) 216:33 DSM-IV 70–120 months AS had language delay and cognitive impairment than autism McConachie et al. (2005) 104 children Modified DSM-IV 24–48 months AS can be reliably diagnosed only after child enters school Smith et al. (2005)…”
BackgroundModeling the Autism Spectrum Disorder Phenotype
McCray, A. T., Trevvett, P., & Frost, H. R. (2013) · Neuroinformatics · doi:10.1007/s12021-013-9211-4 · Cited by 45 · see citing works
“Diagnosis of affected individuals falls on a spectrum, with variability both in the presence or absence of specific autistic features as well as variability in the severity of those features (Tager-Flusberg and Joseph 2003; Walker et al. 2004; Volkmar et al. 2009; Rutter 2011).”
Caring for Children With Autism Spectrum Disorder, Part I: Prevalence, Etiology, and Core Features
Inglese, M. D., & Elder, J. H. (2008) · Journal of Pediatric Nursing · doi:10.1016/j.pedn.2007.12.006 · Cited by 45 · see citing works
“One report describes children with PDDNOS as being “midway between the autism and AD groups on IQ, measures of adaptive behavior, and language milestones” (Walker et al., 2004, p. 178).”
BackgroundInfluentialMørdre, M., Grøholt, B., Knudsen, A. K., Sponheim, E., Mykletun, A., & Myhre, A. M. (2011) · Journal of Autism and Developmental Disorders · doi:10.1007/s10803-011-1319-5 · Cited by 45 · see citing works
“During the last decade, several studies have questioned the adequacy of the current PDD NOS category (Allen et al. 2001; Buitelaar et al. 1999; Volkmar et al. 2009; Walker et al. 2004).”
BackgroundKasari, C. L., & Rotheram-Fuller, E. J. (2005) · Current Opinion in Psychiatry · doi:10.1097/01.yco.0000179486.47144.61 · Cited by 43 · see citing works
Greaves‐Lord, K., Eussen, M. L. J. M., Verhulst, F. C., Minderaa, R. B., Mandy, W., Hudziak, J. J., Steenhuis, M., de Nijs, P. F. A., & Hartman, C. A. (2012) · Journal of Autism and Developmental Disorders · doi:10.1007/s10803-012-1724-4 · Cited by 40 · see citing works
“Autistic Disorder, Asperger’s Syndrome, PDD-not otherwise specified; PDD-NOS) can validly and empirically be distinguished (e.g. Kamp-Becker et al. 2010; Walker et al. 2004; Stevens et al. 2000).”
BackgroundWassenberg, R., Hurks, P. P. M., Hendriksen, J. G. M., FERON, F. J. M., Meijs, C. J. C., Vles, J. S. H., & Jolles, J. (2008) · Journal of Clinical and Experimental Neuropsychology · doi:10.1080/13803390701523091 · Cited by 39 · see citing works
“attention deficit hyperactivity disorder and with pervasive development disorder are especially relevant in this respect because these children have executive problems as well as deficits in understanding certain aspects of complex language (Bruce, Thernlund, & Nettelbladt, 2006; Camarata & Gibson, 1999; Cohen et al.,…”
BackgroundThe role of language and communication impairments within autism
Gernsbacher, M. A., Geye, H. M., & Weismer, S. E. (2005) · Trends in language acquisition research · doi:10.1075/tilar.4.06ger · Cited by 38 · see citing works
Harrop, C., Gulsrud, A. C., & Kasari, C. L. (2015) · Journal of Autism and Developmental Disorders · doi:10.1007/s10803-015-2511-9 · Cited by 40 · see citing works
“RRBs represent an extremely heterogeneous set of behaviors and even within children with ASD there is vast variability in their frequency and intensity of expression (Harrop et al. 2014; Turner 1999; Walker et al. 2004).”
The use of genetic epidemiology to guide classification in child and adult psychopathology
Szatmari, P., White, J., & Merikangas, K. R. (2007) · International Review of Psychiatry · doi:10.1080/09540260701563619 · Cited by 38 · see citing works
“Language and IQ seem to be the most important variables associated with outcome and lack of IS may be the one reliable differentiating feature of autism versus PDDNOS (Walker et al., 2004).”
BackgroundInfluentialCohen, I. L., Gomez, T. R., Gonzalez, M. G., Lennon, E. M., Karmel, B. Z., & Gardner, J. M. (2009) · Journal of Autism and Developmental Disorders · doi:10.1007/s10803-009-0863-8 · Cited by 38 · see citing works
Hattier, M. A., & Matson, J. L. (2012) · Research in Autism · doi:10.1016/j.rasd.2011.12.001 · Cited by 34 · see citing works
Evaluating motor cortical oscillations and age-related change in autism spectrum disorder
Gaetz, W. C., Rhodes, E., Bloy, L., Blaskey, L. G., Jackel, C. R., Brodkin, E. S., Waldman, A. T., Embick, D., Hall, S., & Roberts, T. P. L. (2019) · NeuroImage · doi:10.1016/j.neuroimage.2019.116349 · Cited by 33 · see citing works
“In more severely affected cases, motor stereotypies (e.g., hand flapping, body rocking, etc.) are also common [25-27].”
Upadhyay, J., Patra, J., Tiwari, N., Salankar, N., Ansari, M. N., & Ahmad, W. (2021) · Cells · doi:10.3390/cells10040958 · Cited by 32 · see citing works
“A research study showed that children suffering from PDD-NOS were initially diagnosed with Attention Deficit Hyperactivity Disorder (ADHD) and that they did not differ from ADHD children with respect to all the symptoms of ASD, attention difficulties, or general psychopathology.”
MethodInfluentialGenesis, modelling and methodological remedies to autism heterogeneity
Rabot, J., Rødgaard, E.-M., Joober, R., Dumas, G., Bzdok, D., Bernhardt, B., Jacquemont, S., & Mottron, L. (2023) · Neuroscience & Biobehavioral Reviews · doi:10.1016/j.neubiorev.2023.105201 · Cited by 31 · see citing works
Koyama, T., & Kurita, H. (2008) · Psychiatry and Clinical Neurosciences · doi:10.1111/j.1440-1819.2008.01871.x · Cited by 29 · see citing works
Möricke, E., Willemsen‐Swinkels, S. H. N., Beuker, K. T., & Buitelaar, J. K. (2010) · European Child & Adolescent Psychiatry · doi:10.1007/s00787-010-0103-y · Cited by 28 · see citing works
Measuring the Diagnostic Features of Social (Pragmatic) Communication Disorder: An Exploratory Study
Yuan, H., & Dollaghan, C. A. (2018) · American Journal of Speech-Language Pathology · doi:10.1044/2018_ajslp-16-0219 · Cited by 28 · see citing works
Face and Emotion Recognition in MCDD Versus PDD-NOS
Herba, C. M., de Bruin, E. I., Althaus, M., Verheij, F., & Ferdinand, R. F. (2007) · Journal of Autism and Developmental Disorders · doi:10.1007/s10803-007-0438-5 · Cited by 24 · see citing works
“Walker (1981) reported that children with schizophrenia were less accurate in recognizing emotional expressions compared to the other groups.”
BackgroundMethodInfluentialKlein-Tasman, B., Risi, S., & Lord, C. (2006) · Journal of Autism and Developmental Disorders · doi:10.1007/s10803-006-0266-z · Cited by 24 · see citing works
“It is not surprising that the classification of the children with clinical diagnoses of PDD-NOS yielded lower rates of correct classification in this study, as researchers have consistently lamented the heterogeneity of this diagnostic category (Mahoney et al., 1998; Tanguay, 2000, 2004; Walker et al., 2004 ).”
ResultSyriopoulou–Delli, C. K., & Papaefstathiou, E. (2019) · International Journal of Developmental Disabilities · doi:10.1080/20473869.2018.1542561 · Cited by 24 · see citing works
“In practice, this interpretation is difficult when applied to individuals who vary in terms of quality and quantity in these two domains (Buitelaar et al. 1999, Walker et al. 2004).”
BackgroundFein, D., & Helt, M. (2017) · Journal of the International Neuropsychological Society · doi:10.1017/s1355617717001096 · Cited by 20 · see citing works
“Are RRBs necessary features of ASD, while other frequently comorbid symptoms are ancillary (as in DSM-5)?”
BackgroundInfluentialMotor Functioning in Autistic Spectrum Disorders: A Preliminary Analysis
Behere, A. P., Shahani, L., Noggle, C. A., et al. (2012) · Journal of Neuropsychiatry · doi:10.1176/appi.neuropsych.11050105 · Cited by 20 · see citing works
“500; t [24] 2.”
Arnett, A. B., & Flaherty, B. P. (2022) · Journal of Neurodevelopmental Disorders · doi:10.1186/s11689-022-09454-w · Cited by 20 · see citing works
“Symptom-based subtypes of NDDs, such as the predominantly inattentive versus predominantly hyperactive/impulsive clinical presentations of ADHD or Asperger’s syndrome versus autism or pervasive developmental disorder, have shown poor stability [11], interrater reliability [12], and inconsistent external validity [13].”
BackgroundChen, M., Lin, Y., Yu, C., Fu, R., Shentu, H., Yao, J., Huang, J., He, Y., & Yu, M. (2023) · Archives of Gynecology and Obstetrics · doi:10.1007/s00404-023-07059-9 · Cited by 19 · see citing works
Mercadante, M. T., van der Gaag, R. J., & Schwartzman, J. S. (2006) · Brazilian Journal of Psychiatry · doi:10.1590/s1516-44462006000500003 · Cited by 23 · see citing works
Brennan, L., Barton, M. L., Chen, C. A., Green, J., & FEIN, D. A. (2014) · Journal of Autism and Developmental Disorders · doi:10.1007/s10803-014-2295-3 · Cited by 19 · see citing works
“…research primarily described PDD-NOS in relation to other ASDs in order to examine whether each disorder presented unique and varied profiles or whether each diagnosis differed only by their position along a spectrum of symptom severity (Buitelaar et al. 1999; Paul et al. 2004; Walker et al. 2004).”
InfluentialWhat Is Social about Autism? The Role of Allostasis-Driven Learning
Djerassi, M., Ophir, S., & Atzil, S. (2021) · Brain Sciences · doi:10.3390/brainsci11101269 · Cited by 20 · see citing works
“Future empirical research is called for in order to test whether the distinct neural and behavioral features described here, including perception, motor control, and learning can differentiate autism from typical development and other spectrum disorders in young children [182,183].”
BackgroundBrito, M. C., & Carrara, K. (2010) · Revista da Sociedade Brasileira de Fonoaudiologia · doi:10.1590/s1516-80342010000300018 · Cited by 17 · see citing works
“possui critérios específicos e é utilizada quando as características do sujeito não se adequam a nenhum outro TID(12).”
BackgroundInfluentialAutism Spectrum Disorders: The Role of Genetics in Diagnosis and Treatment
Deutsch, S. I. (2011) · InTech eBooks · doi:10.5772/976 · Cited by 16 · see citing works
Interpretable Machine Learning Reveals Dissimilarities Between Subtypes of Autism Spectrum Disorder
Garbulowski, M., Smolińska, K., Diamanti, K., Pan, G., Maqbool, K., Feuk, L., & Komorowski, J. (2021) · Frontiers in Genetics · doi:10.3389/fgene.2021.618277 · Cited by 15 · see citing works
“In Walker et al. (2004), comparison of autistic symptoms revealed that PDD-NOS is less severe than autism and AS.”
BackgroundResultWISC–III index score profiles of 520 Swedish children with pervasive developmental disorders.
Zander, E., & Dahlgren, S. O. (2010) · Psychological Assessment · doi:10.1037/a0018335 · Cited by 15 · see citing works
Scientific challenges in developing biological markers for autism
Hewitson, L. C. (2013) · OA Autism · doi:10.13172/2052-7810-1-1-474 · Cited by 13 · see citing works
Crespi, B. J. (2011) · Springer eBooks · doi:10.1007/978-94-007-0837-2_7 · Cited by 13 · see citing works
Oeseburg, B., Groothoff, J. W., Dijkstra, G. J., Reijneveld, S. A., & Jansen, D. E. M. C. (2009) · Research in Developmental Disabilities · doi:10.1016/j.ridd.2009.10.018 · Cited by 13 · see citing works
Tanguay, P. E. (2004) · Journal of the American Academy of Child & Adolescent Psychiatry · doi:10.1097/00004583-200402000-00013 · Cited by 13 · see citing works
Harrop, C., Gulsrud, A. C., Shih, W., Hovsepyan, L., & Kasari, C. L. (2015) · Autism · doi:10.1177/1362361315580443 · Cited by 12 · see citing works
“While obligatory for a DSM-5 diagnosis of ASD, RRBs represent an extremely heterogeneous set of behaviors and there is vast variability between children in their frequency and intensity of expression (Harrop et al., 2014; Turner, 1999; Walker et al., 2004; Watt et al., 2008).”
BackgroundPTEN gene mutations in patients with macrocephaly and classic autism: A systematic review.
Abghari, F. Z., Moradi, Y., & Akouchekian, M. (2019) · PubMed Central · doi:10.34171/mjiri.33.10 · Cited by 11 · see citing works
“PDDNOS and Asperger syndrome have milder symptoms than classic autism (1, 2).”
BackgroundComparison of autism spectrum disorder subtypes based on functional and structural factors
Wang, S., Sun, Z., Martínez-Tejada, L. A., & Yoshimura, N. (2024) · Frontiers in Neuroscience · doi:10.3389/fnins.2024.1440222 · Cited by 11 · see citing works
van Rijn, S., de Sonneville, L. M. J., Lahuis, B., Pieterse, J., van Engeland, H., & Swaab, H. (2012) · Journal of Autism and Developmental Disorders · doi:10.1007/s10803-012-1688-4 · Cited by 11 · see citing works
Alotaibi, A. A. G. (2015) · Research Exchange (Washington State University) · Cited by 11 · see citing works
Boterberg, S., Zanatta, A., Moerman, F., Schaubroeck, S., Siew, J., Schryver, M. D., & Roeyers, H. (2022) · Heliyon · doi:10.1016/j.heliyon.2022.e09727 · Cited by 9 · see citing works
“The expression of RRBs in autism is extremely heterogeneous and although some children with autism show certain RRBs at some point during their development, not all children will display them ubiquitously (Turner, 1999; Walker et al., 2004).”
The Impact of DSM-5 on Autism Spectrum Disorder
Tsai, L. Y. (2015) · Psychopathology Review · doi:10.5127/pr.035414 · Cited by 9 · see citing works
“During the last decade, several studies have questioned the adequacy of the current PDDNOS category and the literature so far has been unable to clearly differentiate children with PDDNOS from children with AD (Allen et al., 2001; Volkmar, State, & Klin, 2009; Walker et al., 2004).”
BackgroundUono, S., Sato, W., & Toichi, M. (2012) · Research in Autism · doi:10.1016/j.rasd.2012.10.007 · Cited by 10 · see citing works
“Walker et al. (2004) demonstrated that individuals with PDD-NOS showed milder autistic symptoms and relatively poor daily living skills.”
BackgroundApplying Item Response Theory Modeling to Identify Social (Pragmatic) Communication Disorder
Yuan, H., & Dollaghan, C. A. (2020) · Journal of Speech Language and Hearing Research · doi:10.1044/2020_jslhr-19-00284 · Cited by 8 · see citing works
Avances y perspectivas en Síndrome de Asperger
Flórez, R. A. N. (2014) · Nova · doi:10.22490/24629448.998 · Cited by 8 · see citing works
Deconstruyendo los trastornos del espectro autista: perspectiva clínica
Tuchman, R. F. (2013) · Revista de Neurología · doi:10.33588/rn.56s01.2012657 · Cited by 8 · see citing works
“– Trastorno generalizado del desarrollo no especificado o autismo atípico [9]: proceso en el que la falta de definiciones operativas hace problemática su clasificación y estudio [10-12].”
BackgroundBhat, B. A., Hussain, A. M., Qadir, W., & Dar, S. A. (2019) · doi:10.36648/2472-1786.5.2.82 · Cited by 7 · see citing works
- Authors
- WALKER, D. R., THOMPSON, A., ZWAIGENBAUM, L., GOLDBERG, J., BRYSON, S. E., MAHONEY, W. J., STRAWBRIDGE, C. P., & SZATMARI, P.
- Affiliations
- McMaster University (CA)
- Dalhousie University (CA)
- ORCID
- ZWAIGENBAUM, LONNIE
- Venue
- Journal of the American Academy of Child & Adolescent Psychiatry
- Publisher
- Elsevier BV
- Published
- 2004-02
- Volume
- 43
- Issue
- 2
- Pages
- 172-180
- ISSN
- 0890-8567 (ISSN-L)
- OpenAlex
- W2081876348
- Semantic Scholar
- 94b8b340f54c72f9cb0978275647255a65330777
- Cited by
- 191
- References
- 37
- Citations by year
- 2025: 3 · 2024: 2 · 2023: 6 · 2022: 5 · 2021: 6 · 2020: 1 · 2019: 9 · 2018: 4 · 2017: 7 · 2016: 3 · 2015: 8 · 2014: 14 · 2013: 16 · 2012: 19
- FWCI
- 4.87
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Journal of the American Academy of Child & Adolescent Psychiatry (publishedVersion)
- PubMed (publishedVersion)
- Topics
- Life Sciences › Neuroscience › Cognitive Neuroscience › Autism Spectrum Disorder Research
- Health Sciences › Medicine › Psychiatry and Mental health › Child Nutrition and Feeding Issues
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Genetics and Neurodevelopmental Disorders
- Keywords
- pervasive developmental disorder not otherwise specified, autism spectrum disorder, Asperger syndrome, diagnostic criteria, clinical features, repetitive and stereotyped behaviors, social communication deficits, language delay, cognitive impairment, diagnostic heterogeneity, children
- MeSH terms
- Autistic Disorder, Child, Child Development Disorders, Pervasive, Diagnosis, Differential, Female, Humans, Male, Surveys and Questionnaires, Severity of Illness Index, Asperger Syndrome
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