The Autism Spectrum Disorder (ASD) has traditionally been one of the main focuses of controversy because of the difficulty of knowing how to fit it into the classification of psychopathologies in a clear and permanent way.

Furthermore, with the publication of the Diagnostic and Statistical Manual of Mental Disorders (DSM-V) in 2013, the taxonomy of this psychopathology has been modified with respect to the previous version DSM-IV TR. Specifically, it has gone from being included along with other diagnostic labels within the category of Generalized Developmental Disorders to being established under the name of ASD without distinction. Even so, different levels of affectation (I-IV) have been proposed to be specified in the diagnosis made.

Autism Spectrum Disorders: how to diagnose them?

The early detection of autism is complex , since in most cases it is the parents who give the first warning signs. Authors such as Wing (1980), Volkmar (1985), Gillberg (1990) and Frith (1993), state that the symptoms of autism appear before the age of three but add that it is difficult to detect them during the first year of life.

There is still some difficulty and lack of knowledge regarding the information available in the primary care service that allows for early detection. As indicated in one of the studies carried out in the USA (English and Essex, 2001), it was found that the first to suspect the presence of manifestations that could indicate autistic functioning was the family (60%), followed at a great distance by pediatricians (10%) and educational services (7%). In addition there are multiple manifestations in form and intensity in which this disorder appears in early ages . Even with all these difficulties, early detection can occur around 18 months of age or even earlier.

Tests and tools for ASD detection

Currently, there is no test or medical evidence that by itself indicates whether a person has ASD. The diagnosis of ASD should include complementary observation of the person’s behavior, knowing his or her developmental history, and applying a battery of medical and psychological tests to detect the manifestation of the signs and symptoms of autism.

Some of the tests used for the early detection of Autism are the CHAT of Baron-Cohen (1992), the M-CHAT of Robins, Fein, Barton and Green (2001), the IDEA of Rivière and Martos (1997) and the IDTA-18 of F.J Mendizábal (1993). The age of application of these tests would be between 18 and 36 months.

In addition to the evidence noted above, it is essential to collect information on children’s behaviour from different people and in different contexts by integrating the various data sources in a comprehensive manner and clarifying any discrepancies. The earliest possible detection of any alteration in a child’s development makes it possible to establish an early intervention program capable of promoting the child’s personal and social development to the fullest extent possible, as well as the appropriate guidance of his or her family members. For this purpose it is advisable to rely on the following possible sources of information :

  • Test scales in clinical sessions.
  • Interviews and information from both teachers and parents
  • Observation in natural situations (home, school) and/or structured observations of the interaction with parents and assessed

Symptoms and Criteria for Detecting Autism

To carry out an appropriate evaluation from the age of three , the areas of evaluation described below should be taken into account , together with the tests used for the evaluation of child development (both in clinical and other populations).

Extreme values on the measurement scales, both under and over depending on the test, can be very useful in supplementing the diagnosis of autism or ASD.

1. Social evaluation

It consists of collecting information on social interest, the quantity and quality of social initiatives, eye contact , joint attention, body, vocal and motor imitation, attachment, expression and recognition of emotions. For this purpose, structured interviews with parents are used, such as ADI-R by M. Rutter, A. Le Couteur and C. Lord (1994);

Structured observation in the clinical context of both planned (CARS by DiLalla and Rogers, 1994) and unplanned interactions with the father and mother; videos provided by the family and various clinical instruments (Normative Tests such as the Vinelandde Sparrow, Balla and Cicchetti (1984), Criterial Tests such as the Uzgiris-Hunt, reviewed by Dunts (1980) or Developmental Inventories such as the Battelle, Spanish adaptation by De la Cruz and González (1996).

Some symptoms that can be detected

  • Lack of emotional expression.
  • Isolation with their peers.

2. Communicative assessment

Information is collected on intentionality, communication tools, functions, contents, contexts and understanding . The study uses structured interviews (ADI-R 1994), structured observations (ACACIA by Tamarit 1994, PL-ADOS by DiLavore, Lord & Rutter 1995), family videos and various clinical instruments (such as the Reynell Language Development Scale by Edwards, Fletcher, Garman, Hughes, Letts and Sinka 1997; and the ITPA by Samuel A. Kirk, James J. McCarthy, Winifred D. Kirk, revised edition in 2004, Madrid: TEA), among others.

Some symptoms that can be detected

  • Literal interpretation of sentences.
  • Delayed appearance of verbal communication.

3. Game

Information is collected on exploration, functional play, symbolic play, role-playing and cooperative play . Structured interviews (ADI-R 1994), semi-structured observations (free play), family videos and various clinical instruments are used (Lowe&Costello Symbolic Play Test 1988).

Some symptoms that can be detected

  • Difficulties in understanding the nature of roleplaying
  • Rejection of social play.

4. Cognitive evaluation

Information is collected to make an assessment of the sensorimotor level, the developmental level, evaluation of stimulating and sensory preferences , learning style and potential, executive and metacognitive skills and academic skills.

The following scales can be used: Leiter International Performance Scale, adapted by Arthur in 1980, the Weschler Intelligence Scales (WPPSI-III 2009 and WISC-V 2015), the Bayley Scales of Child Development 1993, the Uzgiris-Hunt Child Development Scale, revised by Dunts in 1980 and the PEP-R (Psychoeducational Profile) by Mesibov, Schopler and Caison 1989.

Some symptoms that can be detected

  • Appearance of an unusually developed cognitive ability
  • General cognitive difficulties.

5. Motor evaluation

Measurement of fine and gross motility by observation, information and application of the Brunet Lezine Scale by O. Brunet and L. Lezine 1951 and/or the PEP-R by Mesibov, Schopler and Caison 1989.

Some symptoms that can be detected

  • Alterations in gait and posture.
  • Alterations in motor anticipation.

6. Family-Environmental Assessment

Knowledge through the family interview of the impact of the diagnosis , its resources to overcome it and establish adequate ways of collaboration in the intervention, the interaction between family and child and the structure of the domestic environment.

7. Medical evaluation

Use of neurological and neuroimaging tests (EEG electroencephalogram, CT scan, SPECT single photon emission tomography, MRI, blood and urine tests, evoked potentials). There should be an absence of localized lesions that could explain the symptoms.

8. Evaluation of personal autonomy

Mainly through interviews and application of questionnaires to parents about feeding, sphincter control, dressing and grooming . One of the most widely used scales is the Lawton and Brody Scale, translated into Spanish in 1993.

9. Assessment of behavioral problems

Assessment of the presence or absence of behavioural problems (disruptive behaviours, aggressions, self-harm, stereotypes, pica, regurgitation, phobias…) their intensity and frequency by means of questionnaires or structured interviews such as the ADI-R 1994, or the ICAP (Inventory of service planning and individual programming) Spanish adaptation by the University of Deusto, Bilbao in 1993.

10. Evaluation of preferences

Knowledge of objects, toys, stimuli, sensory modalities, activities, food , etc. preferred in order to use them as reinforcers or motivators for other relevant activities or communication objectives.

By way of conclusion

As we have seen, the diagnosis of autism must be made on the basis of a thorough clinical evaluation, and must be based strictly on internationally agreed criteria, for three main reasons:

  • Ensure access to appropriate support and intervention services appropriate to the particular case.
  • So that scientific research can be comparable, both in its clinical aspects and especially in the assessment of the effectiveness of the different services and treatments proposed .
  • To guarantee an education that is adequate to the particular needs of the case of the child in question , given that the lack of rigorous diagnostic procedures could lead to the exclusion of children with autism from special services designed for them, as well as to the inclusion of persons with other psychological conditions.

Bibliographic references:

  • International Association Autism-Europe (2000): Description of autism.
  • Jané, M. C. and Doménech-Llaberi, E.(1998): Childhood autism. In González Barrón, R. (coord.) . Psychopathology of the child and adolescent. Madrid: Pirámide, pp. 295-318.
  • Martos-Pérez, J. Revista Neurol; 42 (Supl 2) S99-S101 (2006): Autism, neurodevelopment and early detection.
  • Mendizábal, F. J. (1993): An attempt to approach the subject of early detection in autism. Proceedings of the VII Autism Congress. Editorial Amarú.
  • Pedreira, M. J. (2003): Assessment, diagnosis, neurobiology and treatment of autism. Madrid: Edición Laertes.
  • Rivière, A. Autism and Pervasive Developmental Disorders In A. Marchesi, C. Coll and J. Palacios Eds. (1999): Psychological Development and Education III. Madrid: Alianza Psicología, pp. 329-360.