New Zealand Autism Spectrum Disorder Guideline - Ministry of Health

Part 1: Diagnosis and initial assessment of ASD
Part 1
• assessment of adaptive functioning (those
skills needed for independent living), also
in order to better understand the person’s
abilities (note that professional tests users
should be aware of ASD norms for the
Vineland adaptive behaviour scales 47 and
other ASD relevant research 48-50 )
• assessment of other forms of cognitive
functioning (see below)
• neurological assessment
• mental health assessments
• communication and audiological assessment
• sensory, motor and perceptual assessments
• vision assessment
• occupational and physical therapy evaluation
• evaluation of social competence and
functioning
• evaluation of interests and activities
19 33
• assessment of family resources and needs
34 41 42 51-54
(Recommendation 1.2.4).
The use of standardised interviews and
assessment formats for autism, Asperger
syndrome and ASD is supported 55 , and
assessment processes are regularly reviewed
and refined as understanding of ASD develops
further 56-59 (Recommendation 1.2.5). Currently,
commonly recommended tools include:
• Autism Diagnostic Interview – Revised
(ADI-R), a standardised, semi-structured
clinical review for carers of children and
adults suspected of having autism or other
58 60-62
pervasive developmental disorders
• Autism Diagnostic Observation Schedule
– Generic (ADOS-G), a semi-structured,
standardised assessment of social interaction,
communication, play and imaginative use
of materials, for use with children and
adults suspected of having autism or other
58 63 64
pervasive developmental disorders
• Asperger Syndrome Diagnostic Interview,
a clinician-administered tool for use with
children and adults suspected of having
Asperger syndrome or High Functioning
Autism 65
• Autism Spectrum Disorder Screening Adults
Questionnaire (ASDASQ), a screening test for
ASD in the adult population 66
• Autism Spectrum Quotient (AQ), a selfadministered
screening test for people
suspected of High Functioning Autism/
Asperger syndrome 67
• Australian Scale for Asperger’s syndrome
(ASAS), a checklist for parents of primary
school children suspected of having Asperger
syndrome 68
• Childhood Asperger Syndrome Test (CAST),
a parent-completed screening test for children
aged 5–11 years 69
• Developmental, Diagnostic and Dimensional
Interview (3di), a computerised assessment
for autism spectrum disorders 70
• Diagnostic Interview for Social and
Communicative Disorders (DISCO),
a clinician-administered schedule of
71 72
assessment for use with people of all ages
• Gilliam Asperger’s Disorder Scale (GADS),
a scale for use by parents and professionals,
assessing Asperger syndrome in people aged
3–22 years 73
• Krug Asperger’s Disorder Index (KADI),
a scale for use by professionals, assessing
Asperger syndrome in people aged 6–22
years 74 .
Many of the tests above are subject to ongoing
review and limitations are described in the
literature and Appendix 5. Many of the
tools require specialist education which
is not currently available in New Zealand
(Recommendation 1.2.6, Recommendation 6.2,
Professional learning and development).
Theory and research on the nature of ASD is
complex, controversial and ongoing 75 76 . The
three main theoretical approaches are:
• disturbance in theory of mind or
‘mindblindness’: impaired ability to reflect on
the contents of one’s own and others’ minds 77
• weak central coherence theory: the difficulty
that people with ASD have in cognitively
‘seeing the big picture’, and their focus on the
smallest possible parts
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New Zealand Autism Spectrum Disorder Guideline