cFrequently, various questions are received in consultation regarding the diagnosis of: how is it diagnosed? Is having “autism spectrum” the same as “autism”? My patient was diagnosed with “pervasive developmental disorder not otherwise specified”, is it “less” than “autism”?
Through this article I hope to answer these frequently asked questions.
Brief overview of autism as a diagnostic entity from the American Psychiatric Association
Autism appears for the first time as a diagnostic entity for the American Psychiatric Association (APA) in the 1980s, with the publication of the Diagnostic and Statistical Manual of Mental Disorders in its third edition (DSM III), under the name childhood autism.
With the publication of the DSM-IV (1994) and its revised version (DSM-IV TR, 2000), it appears within the generalized developmental disorders, where the following subtypes were expressed:
- autistic disorder
- Rett disorder (or Rett syndrome)
- childhood disintegrative disorder (IDD)
- Asperger’s disorder (or Asperger’s syndrome)
- pervasive developmental disorder not otherwise specified (PDD not otherwise specified)
These PDDs, in turn, were part of what was called at the time: “disorders of onset in infancy, childhood or adolescence.”
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With the (American Psychiatric Association, 2013) and the (World Health Organization, 2018), these disorders are now called neurodevelopmental disorders, or neurodevelopmental disorders, an entity that has regained a lot of weight in recent years.
Neurodevelopmental Disorders are understood as “a heterogeneous group of related chronic disorders, which manifest in early childhood, generally before entering primary school, and which together share an alteration in the acquisition of cognitive and motor skills. , language, learning and behavior that significantly impacts personal, social and academic functioning” (Fejerman and Grañana, 2017, p.27).
With the publication of the DSM – V and the ICD – 11 These disorders are now called neurological developmental disorders, or neurodevelopmental disorders, an entity that has regained much importance in recent years.
Among these disorders is ASD, a term that has completely replaced PDD. All PDD subtypes become part of it, with the exception of Rett syndrome, which became independent and appears in ICD-11 as a developmental abnormality along with Prader Willi syndrome and other genetic alterations. In the DSM-V Diagnostic Criteria Consultation Guide (APA, 2014) it is clarified that all diagnoses under the name of Asperger syndrome, Autism and unspecified PDD, according to the name of the previous version of said manual, must be renamed ASD.
Autism spectrum disorder from ICD 11 and DSM V
According to the WHO (2018), ASD It is characterized by persistent deficits in the ability to initiate and maintain reciprocal social interaction and social communication. Added to this is a range of behavior patterns and interests that are restricted, repetitive and lack flexibility. Being part of neurodevelopmental disorders, its onset generally occurs in early childhood, but symptoms may not fully manifest until later, when social demands exceed developmental capabilities. Here we can see why in many cases these behaviors can be identified when the child enters formal schooling, between 4 and 5 years of age.
The WHO (2018) states that the deficits in ASD are so serious that they can cause deterioration in different areas: in personal, family, social, educational, occupational functioning or other significant areas of functioning. Furthermore, it can be observed that this mode of behavior is verifiable in all the environments where the individual operates, although they may vary according to social, educational or other contexts.
The DSM-V instead classifies them in terms of severity according to the degree of help required.
The ICD-11 proposes the following classification within ASD:
- autism spectrum disorder without intellectual developmental disorder and with mild or no functional language impairment
- autism spectrum disorder with intellectual developmental disorder and mild or no functional language impairment
- autism spectrum disorder without intellectual developmental disorder and with poor functional language
- autism spectrum disorder with intellectual developmental disorder and poor functional language.
- autism spectrum disorder without intellectual developmental disorder and with absence of functional language
- autism spectrum disorder with intellectual development disorder and absence of functional language.
- other specified autism spectrum disorder
- autism spectrum disorder, unspecified
The DSM-V, on the other hand, classifies them in terms of severity according to the degree of help required in each affected domain, whether in restricted behaviors and interests or in social communication, classifying them as follows: requires support, requires substantial support and requires very substantial support (APA, 2014).
For the diagnosis of ASD according to this manual, the following is taken into account:
Differential diagnosis
Although this will not be discussed in depth, it is important to consider the following tables for differential diagnosis (APA, 2014; Fejerman and Grañana, 2017):
- progressive encephalopathies.
- epileptic encephalopathies.
- global developmental delay.
- intellectual disability.
- social communication disorder (pragmatic).
- specific language disorder.
Instruments of inquiry
The ASD inquiry and diagnosis instruments – and in all areas – allow us to collect information in different ways, either by direct observation of the individual or by information provided to referents (parents, guardians, caregivers, teachers, etc.).
For correct use and interpretation of the results, it is necessary that the person using these instruments be instructed and have experience in their use, as well as in the presentation of results and their interpretation.
ANDIt is necessary that the information expressed in the reports has everything required so that other professionals can recognize where the results come from.
The first allows the margin of error in the use of tests to decrease. With respect to the modes of presentation of the results, it is necessary that the information expressed in the reports has everything required so that other professionals can recognize where the results come from (in psychometric tests, for example, conversion of scores, level of impact, numbers of deviations from the mean, performance profile, etc.). This allows, among other things, to monitor and reevaluate treatment plans.
In relation to interpretation, it is necessary that the person who uses the results has updated training on what is being evaluated, in order to be able to construct observables based on the data that was collected throughout the entire process. We must remember that the interpretation of the profiles must be done based on each case, and that we cannot refer only to the results of the tests that have been provided, because in many cases they can yield false negatives (that is, , wrongly indicating the absence of alterations) or false positives (erroneously indicating the presence of alterations) (Puerta, 2004).
Two-level inquiry instruments Fejerman and Grañana (2017):
Level 1: made up of investigative evidence or screening They seek to quickly investigate whether there are warning signs in development (in the case of ASD). They generally have a cut-off score which, if exceeded, results in a positive investigation, which would demand a deeper investigation. A test of screening No It is used for diagnosis in no case. It only allows certain risk indicators in development to be identified.
Continuing with what was proposed by the authors, at this level an evaluation of development routine by health professionals: here tests such as Denver II, Pediatric Emotional Distress Scale (PEDS), Child Development Inventory (CDI), Age and Stage Scale (ASQ) can be used.
A test of screening No It is used for diagnosis in no case
In case of suspected autism: Various instruments can be used, such as CHAT, Pervasive Developmental Disorders Screening Test (PDDST), Australian Asperger Syndrome Scale (EASA), AUTISM SQ, Social Communication Questionnaire (SCQ). Several of these instruments have age parameters, which must be considered for their use.
Level 2: made up of tests of diagnostic utility that investigate in more depth evolutionary characteristics and characteristic behavioral patterns in cases of ASD.
- Observation: Autistic Behavior Observation Scale 2nd Edition (ADOS 2), Childhood Autism Rating Scale (CARS), 2-Year-Old Autism Screening Test (STAT)
- Surveys: Autism Diagnostic Interview-Revised (ADI-R), Parent Autism Interview (PIA), Gilliam Autism Rating Scale (GARS 2), PDD Screening Test (PDDST-3)
- Neuropsychological Evaluation: (cognitive, adaptive level – Vineland II or III, etc.)
- Complementary medical studies: EEG, auditory study, routine genetic study, fMRI, medical studies according to results obtained (Grañana and Fejerman, 2017; some added by the author of the article).
The importance of ecological validity of tests
Although we have different instruments of inquiry, it is important to add to the diagnostic process the contributions of the references that are part of the context in which the child develops. At the same time, behavioral observation in different contexts is important. Screening tests, whether 1st or 2nd level, may have false positives or false negatives: that means that they may or may not establish autism spectrum scores without the person presenting the condition; The risk of falling into erroneous diagnoses decreases with the study of behavior in this way, as well as adding professionals from various areas (medical in general, mental health, education), the adults responsible for the child, as well as a vast Knowledge of neurodevelopment and semiology can allow an appropriate diagnosis and thus propose a therapeutic plan that adapts to the needs of the individual.
behavioral observation is important in different contexts
Leibovich and Schmidt…