The Role of Medical (including Psychiatric) Evaluations in the Diagnosis of ASD:from Gold-Standard Instruments to Full Diagnosis
Objectives: To present data from an “ASD Complex Diagnosis Program” where a full psychiatric evaluation is conducted in addition to a full ASD-related evaluation in cases in diagnostic doubt after a general Child Psychiatrist and/or Neuropaediatrician evaluation.
Methods: 180 patients consecutively attended in a Specialized consultative care (Tertiary Tier) Child Psychiatry Program for the assessment of children and adolescents with the suspicion of having an ASD diagnosis, underwent a full psychiatric and developmental evaluation. Final best-estimate diagnosis following DSM/ICD criteria was reached after i) evaluation of all life-time medical, educational and psychological reports ii) full psychiatric history with the patient and primary carer iii) full developmental history with the primary carer (roughly 50 % of the times with the ADI-R) iv) ADOS-2 evaluation v) psychopathological assessment including mental state vi) cognitive/language assessment if not available vii) family and teacher questionnaires for the assessment of ASD-behaviors, particularly in relation with peer-relationships vii) other questionnaires as appropriate viii) medical specialists consultation when indicated.
Results: main reasons for referral were: young children referred for a differential diagnosis with Specific Language Disorder, Intelligence Developmental Disorder or emotional and/or behavioral disorders; children/adolescents with multiple previous diagnoses; adolescents for differential diagnosis with psychotic disorders or personality disorders. 85 % of the patients were male; 78 % were up to 9 years of age and 22 % were 10-18 years old. Roughly 50 % were elegible for module 3 of the ADOS-2 (complex language level and up to early adolescence). There was a deviation to the left in the distribution of IQ, with 51 % of the patients having a below average IQ (<70). 80 % of the full sample was given an ASD diagnosis. However, among children/adolescents 8-15 years of age only 58% were given a diagnosis of ASD; behavioural disorder (including severe ADHD), social communication disorder and specific language disorders followed in frequency. Among adolescents 16-18 years of age, 62 % were diagnosed with an ASD, followed by other psychiatric disorders (high-risk of psychosis, personality disorders) and specific language disorders.
Conclusions: a full psychiatric evaluation seems to be an important add-on for the proper diagnosis of children and adolescents with complex developmental/behavioral difficulties.