Early diagnosis of autism spectrum disorder: stability and change in clinical diagnosis and symptom presentation
TLDR
Stability was documented for children diagnosed at 19 months on average, although a minority of children initially showed unclear diagnostic presentations, and findings highlight utility of the ADOS-T in making early diagnoses and predicting follow-up diagnoses.Abstract:
Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by impairments in social communication and interaction, and the presence of restricted and repetitive behaviors and interests Although evidence suggests that ASD has genetic causes (O’Roak & State, 2008), diagnosis relies on observations of behavioral manifestations The average age of diagnosis remains well over three (Mandell, Novak, & Zubritsky, 2006), although the American Academy of Pediatrics recommends that all children be screened for ASD much earlier–at 18 and 24 months (Johnson & Myers, 2007) There is a clear need for diagnostic tools and practices for children who screen positive at these young ages However, because diagnosis in toddlers is relatively new, clinicians face a number of important challenges that warrant further research The stability of early diagnoses, the utility of diagnostic tools for toddlers, and patterns of symptom change in the first few years of life are among a number of questions critical to professionals making early diagnoses
Stability of Early Clinical Diagnoses of ASD
High rates of stability of the broader diagnosis of ASD (rather than specific diagnoses within the spectrum) have been demonstrated in children first diagnosed by age three or older, with estimates ranging from 80 to 100% (see Woolfenden, Sarkozy, Ridley, & Williams, 2012 for a review) However, some estimates for children diagnosed under age three are lower and findings are more variable, ranging from 54 to 100% While 4 of the 11 studies of children diagnosed with Autistic Disorder or ASD under age three reviewed by Woolfenden and colleagues (2011) reported a 100% stability rate, two studies reported rates under 70% (Stone et al, 1999; Turner & Stone, 2007)
In addition to being disparate, these findings may not generalize well to the larger population of toddlers with ASD, as they have consisted of high-risk children (ie, those with an older sibling with ASD or who are referred because of parental or professional concern), or included only relatively lower-functioning children Thus, there is a need to examine diagnostic stability in samples screened in the community that yield participants diverse in symptoms and developmental functioning who may not garner parent or professional concern Findings also need to be extended to younger children, because although children are being screened at increasingly younger ages, just two studies of diagnostic stability have included children under age two Encouragingly, both studies reported 100% stability for initial diagnoses of ASD (Chawarska, Klin, Paul, Macari, & Volkmar, 2009; Cox et al, 1999) However, neither study reported on stability of children with unclear diagnostic presentations at these young ages
Accuracy of Diagnostic Tools for Young Children
Most studies utilize clinical best-estimate diagnoses made by experienced clinicians, a practice that remains the gold standard for diagnosing ASD (Volkmar, Chawarska, & Klin, 2005) However, a standardized observation is crucial to inform clinical diagnosis (Lord & Bishop, 2010) Among the most widely used and validated tools is the Autism Diagnostic Observation Schedule (ADOS; Lord, Rutter, DiLavore, & Risi, 1999) However, it has limited utility with toddlers, as it has unacceptable specificity in children with nonverbal mental ages below 16 months (Gotham, Risi, Pickles, & Lord, 2007)
The ADOS – Toddler Module (ADOS-T) was developed to address these limitations (Lord, Luyster, Gotham, & Guthrie, 2012) and demonstrated excellent sensitivity and specificity in the validation study (Luyster et al, 2009) There is a need to examine its utility in other samples as the validation sample included only high-risk children Of additional importance is the predictive validity of the “ranges of concern,” which its authors recommend to index risk for ASD While these concern ranges were shown to be largely consistent with concurrent clinical diagnosis (Luyster et al, 2009), their utility in predicting later diagnosis has yet to be examined
Symptom Severity Change in Young Children
Another issue critical to the evaluation of toddlers is symptom change within the first years of life, as symptom severity may be more variable than diagnostic status Clinicians may observe significant changes in the frequency and severity of symptoms as the clinical presentation of ASD unfolds, further complicating early diagnosis However, existing evidence is still emerging and findings are relatively inconsistent
Improvement of social communication skills, such as joint attention, response to name, and verbal communication, has been reported (Nadig et al, 2007; Sullivan et al, 2007; Yoder, Stone, Walden, & Malesa, 2009), although stability in more global measures of social symptom severity has also been found (Chawarska, Klin, Paul, & Volkmar, 2007) Evidence exists for other trajectories, including plateauing (ie, developmental slowing) or even worsening (ie, loss) of these skills in a subgroup of children (Landa, Holman, & Garrett-Mayer, 2007; Lord, Luyster, Guthrie, & Pickles, 2012; Ozonoff, Heung, Byrd, Hansen, & Hertz-Picciotto, 2008) Greater understanding of changes in symptom severity in toddlers would inform studies of diagnostic stability, as changes in symptoms are likely to accompany movement on or off the autism spectrum, but may also be observed in children with stable diagnostic presentations
The purpose of this study was to examine stability of clinical diagnosis and symptom presentation, and the utility of a diagnostic tool in making a clinical diagnosis The study utilized a prospectively-identified community sample that received a diagnostic evaluation at 15–24 months of age and a follow-up evaluation at least one year later The specific research aims were to examine the (1) short-term stability of clinical diagnoses, (2) concurrent and predictive utility of ADOS-T classifications and scores, and (3) short-term change in symptom severityread more
Citations
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Behavior profiles of children with autism spectrum disorder in kindergarten: Comparison with other developmental disabilities and typically developing children
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Dissertation
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Risk for ASD in Preterm Infants: A Three-Year Follow-Up Study
Ayelet Harel-Gadassi,Edwa Friedlander,Maya Yaari,Benjamin Bar-Oz,Smadar Eventov-Friedman,David Mankuta,Nurit Yirmiya +6 more
TL;DR: Earlier gestational age and lower general developmental abilities were associated with elevated ASD risk among preterm children, and the long-term risk for ASD was higher when parental reports were employed compared to observational instruments.
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References
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Journal ArticleDOI
The autism diagnostic observation schedule-generic: a standard measure of social and communication deficits associated with the spectrum of autism.
Catherine Lord,Susan Risi,Linda Lambrecht,Edwin H. Cook,Bennett L. Leventhal,Pamela C. DiLavore,Andrew Pickles,Michael Rutter +7 more
TL;DR: Algorithm sensitivities and specificities for autism and PD DNOS relative to nonspectrum disorders were excellent, with moderate differentiation of autism from PDDNOS.
Journal ArticleDOI
Mullen Scales of Early Learning
TL;DR: The Mullen Scales of Early Learning (MSEL) as mentioned in this paper includes five scales that provide information on cognitive and motor ability, including Gross Motor (0-33 months only), Visual Reception, Fine Motor, Expressive Language and Receptive Language.
Journal ArticleDOI
Identification and Evaluation of Children With Autism Spectrum Disorders
TL;DR: This report addresses background information, including definition, history, epidemiology, diagnostic criteria, early signs, neuropathologic aspects, and etiologic possibilities in autism spectrum disorders, and provides an algorithm to help the pediatrician develop a strategy for early identification of children with autism Spectrum disorders.
Journal ArticleDOI
The Autism Diagnostic Observation Schedule: Revised Algorithms for Improved Diagnostic Validity
TL;DR: Reflecting recent research, the revised algorithm now consists of two new domains, Social Affect and Restricted, Repetitive Behaviors, combined to one score to which thresholds are applied, resulting in generally improved predictive value.
Journal ArticleDOI
Autism from 2 to 9 years of age.
TL;DR: D diagnostic stability at age 9 years was very high for autism at age 2 years and less strong for pervasive developmental disorder not otherwise specified and Judgment of experienced clinicians, trained on standard instruments, consistently added to information available from parent interview and standardized observation.