New guidance will bring benefits of evidence-based management to children and young people with ASD, explain Dr Iain McClure (left) and Professor Anne O’Hare

Autism spectrum disorders (ASD—the group of developmental disorders that includes autism, Asperger syndrome, and atypical autism) have been the subject of increasing professional and public interest over the past decade. In a recent study in the South Thames region of the UK,1 the total prevalence of ASD in children aged 9–10 years was 116.1 per 10,000 — these results suggest that ASD, one of the most serious and complex neurodevelopmental disorders, is now also one of the most common. Evidence has emerged that the cost of ASD multi-agency services is potentially immense.2

In Scotland, there are significant disparities in multi-agency ASD provision3 and expert opinion has argued that, for the UK in general, much-needed investment in ASD services is falling behind evidenced need.4

Why is a guideline needed?

The Autistic spectrum disorders needs assessment report from the Public Health Institute of Scotland (PHIS) recommended in 2001 that the Scottish Intercollegiate Guidelines Network (SIGN) should develop a guideline to improve assessment and management of autism spectrum disorders in Scotland.5 This was followed, in 2003, by the publication of the National Autism Plan for Children in England and Wales, which highlighted the need for a systematic approach to ASD assessment, diagnosis, and intervention.6

In the light of these key documents and this context, the aim of clinicians and multi-agency professionals in Scotland was to collaborate to produce an evidence-based guideline for healthcare and other professionals dealing with ASD surveillance, assessment, clinical interventions, and subsequent service evaluation. They also wanted to advise the research community about the pressing gaps in the evidence, from the clinical perspective. The SIGN guideline on ASD in children and young people was published in 2007.7 Although the guideline is primarily aimed at healthcare professionals who specialise in ASD, it also contains helpful information and advice for those working in primary care. They may encounter children and young people they suspect might have ASD or who have already been diagnosed and require appropriate clinical and multi-agency intervention.

How robust is the evidence?

The SIGN guideline includes recommendations, graded from A to D according to strength of the evidence found after an extensive literature search (see Figure 1,). Where there was insufficient evidence available, the guideline development group has provided good practice points (GPPs) to guide clinicians.

As with all behaviour disorders that have no biological markers of pathology, ASD is less amenable to quantitative scientific research than purely physical diseases or conditions. The implication of this is that there is far less evidence on ASD that qualifies for B grade recommendations (or above) than is the case with most other SIGN guidelines.

In addition, a large amount of the research into ASD over the past 10 years (the evidence period searched by SIGN) has been of varying quality; for example, in terms of the reliability and validity of ASD diagnosis for participants in research studies. To address this variation in validity, the development group has (for the first time in an ASD guideline) published a sliding scale of ASD assessment quality. In order to achieve consistency within the guideline, the working party group agreed that three parts of the assessment process were important in the accurate diagnosis of ASD. These are:

  • using a recognised process of obtaining information, usually by multidisciplinary or multiagency personnel
  • mapping the resulting information into a recognised system (e.g. DSM-IV or ICD-10)
  • using a recognised and published diagnostic instrument.

Any paper that did not record diagnosis in this way was downgraded according to the Annex 1 table in the SIGN guideline.7 In addition to the assessment criteria, Annex 1 rates the components of a reliable diagnosis according to increasing accuracy and reliability—from diagnosis simply stated, being the least reliable, to a diagnosis incorporating all three elements of the assessment process, as the most reliable.

Figure 1: Key to evidence statements and grades of recommendations

Levels of Evidence

1++ High quality meta-analyses, systematic reviews of RCTs, or RCTs with a very low risk of bias.
1+ Well conducted meta-analyses, systematic reviews of RCTs, or RCTs with a low risk of bias.
1- Meta-analyses, systematic reviews of RCTs, or RCTs with a high risk of bias.
2++ High quality systematic reviews of case control or cohort studies.
High quality case control or cohort studies with a very low risk of confounding or bias and a high probability that the relationship is causal.
2+ Well conducted case control or cohort studies with a low risk of confounding or bias and a moderate probability that the relationship is causal.
2- Case control or cohort studies with a high risk of confounding or bias and a significant risk that the relationship is not causal.
3 Non-analytic studies, e.g. case reports, case series.
4 Expert opinion.
Grades of Recommendation
Note: The grade of recommendation relates to the strength of the evidence on which the recommendation is based. It does not reflect the clinical importance of the recommendation.
A At least one meta-analysis, systematic review of RCTs, or RCT rated as 1++ and directly applicable to the target population; or
  A body of evidence consisting principally of studies rated as 1+, directly applicable to the target population, and demonstrating overall consistency of results.
B A body of evidence including studies rated as 2++, directly applicable to the target population, and demonstrating overall consistency of results; or
  Extrapolated evidence from studies rated as 1++ or 1+
C A body of evidence including studies rated as 2+, directly applicable to the target population and demonstrating overall consistency of results; or
  Extrapolated evidence from studies rated as 2++.
D Evidence level 3 or 4; or
  Extrapolated evidence from studies rated as 2+.
Good practice points
? Recommended best practice based on the clinical experience of the guideline development group.
RCT=randomised controlled trials
Reproduced from Assessment, diagnosis and clinical interventions for children and young people with autism spectrum disorders by kind permission of SIGN

Screening for autism spectrum disorders

In view of the lack of evidence to support the robustness of ASD screening instruments, the SIGN guideline does not recommend population screening for ASD (Grade C). 8,9

Pre-diagnosis assessment

Healthcare professionals should make the early identification of children requiring further assessment for ASD and other developmental disorders part of their core programme of child health surveillance.7 The guideline from SIGN includes warning signs that should alert healthcare professionals to the possibility of ASD in:
  • pre-school children (Table 1)
  • school-age children (Table 2)
  • adolescents (Table 3).7

Clinical assessment should incorporate a high level of vigilance for features suggestive of ASD, in the areas of social interaction and play, speech and language development, and behaviour (Grade D). However, two possible screening instruments, the CHecklist for Autism in Toddlers (CHAT)10,11 and the modified CHAT (M-CHAT),12 were not recommended by SIGN as being sufficiently reliable to rule out the presence of ASD in very young children, although they can be used as part of a monitoring scheme to identify clinical features indicative of an increased risk of ASD (Grade D).7

The advice to primary care professionals is that monitoring for ASD should be included in the routine assessment of children and young people with delayed development, behavioural and emotional problems, or genetic syndromes. In addition, ASD should be included in the differential diagnosis for very young (pre-school) children who lack normal developmental features, and who are at an age when behaviour typical of ASD may not be obvious (Grade D).7

Table 1: General developmental warnings of possible autism spectrum disorders in pre-school children

Warning signs:

  • Delay or absence of spoken language
  • Looks through people; not aware of others
  • Not responsive to other people’s facial expression/feelings
  • Lack of pretend play; little or no imagination
  • Does not show typical interest in or play near peers purposefully
  • Lack of turn-taking
  • Unable to share pleasure
  • Qualitative impairment in non-verbal communication
  • Does not point at an object to direct another person to look at it
  • Lack of gaze monitoring
  • Lack of initiation of activity or social play
  • Unusual or repetitive hand and finger mannerisms
  • Unusual reactions, or lack of reaction, to sensory stimuli
Adapted from Assessment, diagnosis and clinical interventions for children and young people with autism spectrum disorders by kind permission of SIGN

Table 2: Warnings of possible autism spectrum disorders in school-age children

Warning signs: Communication impairments

  • Abnormalities in language development including muteness
  • Odd or inappropriate prosody
  • Persistent echolalia
  • Reference to self as ‘you’, ‘she’ or ‘he’ beyond three years
  • Unusual vocabulary for child’s age/social group
  • Limited use of language for communication and/or tendency to talk freely only about specific topics

Social impairments

  • Inability to join in play of other children or inappropriate attempts at joint play (may manifest as aggressive or disruptive behaviour)
  • Lack of awareness of classroom ‘norms’ (criticising teachers, overt unwillingness to cooperate in classroom activities, inability to appreciate or follow current trends)
  • Easily overwhelmed by social and other stimulation
  • Failure to relate normally to adults (too intense/no relationship)
  • Showing extreme reactions to invasion of personal space and resistance to being hurried

Impairments of interests, activities and/or behaviours

  • Lack of flexible cooperative imaginative play/creativity
  • Difficulty in organising self in relation to unstructured space (e.g. hugging the perimeter of playgrounds, halls)
  • Inability to cope with change or unstructured situations, even ones that other children enjoy (school trips, teachers being away, etc)

Other factors

  • Unusual profile of skills/deficits
  • Any other evidence of odd behaviours including unusual responses to sensory stimuli
Reproduced from Assessment, diagnosis and clinical interventions for children and young people with autism spectrum disorders by kind permission of SIGN

Table 3: Additional warnings of possible autism spectrum disroders in adolescents*

NB difficulties are likely to be more subtle in older individuals or those without learning disability.

Warning signs:
General picture

  • Long standing difficulties in social behaviours, communication and coping with change, which are more obvious at times of transition (e.g. change of school, leaving school)
  • Significant discrepancy between academic ability and ‘social’ intelligence, most difficulties in unstructured social situations, e.g. in school or work breaks
  • Socially ‘naïve’, lack common sense, not as independent as peers

Language, non-verbal skills and social communication

  • Problems with communication, even if wide vocabulary and normal use of grammar. May be unduly quiet, may talk at others rather than hold a to-and-fro conversation, or may provide excessive information on topics of own interest
  • Unable to adapt style of communication to social situations, e.g. may sound like ‘a little Professor’ (overly formal), or be inappropriately familiar
  • May have speech peculiarities including ‘flat’, unmodulated speech, repetitiveness, use of stereotyped phrases
  • May take things literally and fail to understand sarcasm or metaphor
  • Unusual use and timing of non-verbal interaction (e.g. eye contact, gesture and facial expression)

Social problems

  • Difficulty making and maintaining peer friendships, though may find it easier with adults or younger children
  • Can appear unaware or uninterested in peer group ‘norms’, may alienate by behaviours that transgress ‘unwritten rules’
  • May lack awareness of personal space, or be intolerant of intrusions on own space

Rigidity in thinking and behaviour

  • Preference for highly specific, narrow interests or hobbies, or may enjoy collecting, numbering or listing
  • Strong preferences for familiar routines, may have repetitive behaviours or intrusive rituals
  • Problems using imagination, e.g. in writing, future planning
  • May have unusual reactions to sensory stimuli, e.g. sounds, tastes, smell, touch, hot or cold
*Developed by the guideline group based on their knowledge of the evidence base and their clinical experience Reproduced from Assessment, diagnosis and clinical interventions for children and young people with autism spectrum disorders by kind permission of SIGN

Post-diagnosis monitoring

Healthcare professionals are advised in the guideline of the need for routine checking for co-morbid problems following diagnosis of ASD in children and young people. Where necessary, assessment should seek to identify and manage co-morbid problems accurately (Grade C). In addition, these children and young people may have medical problems or emotional difficulties/disorders that healthcare professionals need to be aware of. The same range of therapeutic interventions should be available to them as to any other child (GPP).


If it is thought possible that a child or young person has ASD, based on initial examination, referral for specialist assessment is advised (GPP). If the diagnosis remains uncertain, and despite the findings of earlier investigations, referral for ASD assessment can be considered at any age (GPP).7


The SIGN guideline reviews the evidence for an extensive array of non-pharmacological and pharmacological interventions. These are mainly for specialist reference, but some interventions are parent-based. Primary care clinicians will find it useful to consult the guideline about levels of evidence for these interventions, in order to inform consultations with parents who are interested in what has been found to work and what has not.

Non-pharmacological interventions

The guideline found limitations of various non-pharmacological interventions, such as some intensive behaviour therapies and auditory integration training, which it does not recommend (Grade A). It found evidence that interventions to support social communication should be considered for children and young people with ASD, providing that the most appropriate intervention was assessed on an individual basis. Also the guideline reports evidence that behavioural interventions should be considered to address a wide range of specific behaviours in children and young people with ASD (Grade B), such as aberrant behaviours (e.g. self-injury, aggression) language skills, academic skills, and social skills.

While parents regularly complain that their children with ASD do not sleep well and/or that they have a range of sensory and coordination difficulties, insufficient evidence was found regarding these areas to make recommendations. Instead the guideline group advises that behavioural therapy should be considered for children and young people with autism who have sleep disturbance (GPP), and that children and young people affected by ASD may benefit from occupational therapy for generic indications (GPP).

In addition, parents may consult their GP about treatments that have received intense media coverage, yet lack a robust scientific basis, such as ‘biomedical’ and nutritional interventions. The SIGN guideline has not been able to provide guidance on these treatments as a result of the current lack of evidence for these approaches, except to advise some good practice points. However, SIGN has included, for the first time in an ASD guideline, a comprehensive list of the search terms used in gathering all the evidence. It is to be hoped that this will reassure those parents who may be concerned that SIGN has ignored such possible interventions. Primary care practitioners can also consult this list on behalf of parents and explain to them that, at this stage, evidence for the intervention sought is insufficient, but that SIGN will reconsider it on revision of the guideline (usually every 3 years).

Pharmacological interventions

Some children and young people with ASD may experience a reduction in symptoms following pharmacological interventions. The advice from SIGN is that pharmacotherapy of children with ASD should only be undertaken by clinicians with appropriate training and access to pharmacy or other support as required (GPP).

The guideline explains the limited clinical indications for specialist use of risperidone and methylphenidate (Grade B), and melatonin (Grade D). This information will be useful to GPs who are invited to support specialist services by shared-care arrangements.

Information and support

The guideline provides a checklist for the appropriate provision of services and information for ASD (Table 4). This should assist primary care health professionals in acting as advocate, on behalf of patients and their families, in situations where services and/or information appear to be inadequate. The guideline also includes information on useful websites, addresses, and reading material for parents and young people.

Shortened versions of the guideline for parents/carers and also for young people, will be available early in 2008.

Table 4: Checklist for provision of services and information

Before assessment

Initial professional concerned (e.g. health visitor, teacher, GP) should:
  • explain to child/young person and parent/carer that a child/young person’s behaviour shows various ‘clinical clues’ that may suggest the possibility of an autism spectrum disorder or a social interaction or social communication difficulty (see Tables 1, 2 and 3)
  • discuss the advantages and disadvantages of further assessment with the parent/carer (and young person, as appropriate) as they see it and check that they have agreement to organise this
  • healthcare professionals should enquire about any other information which might represent evidence of comorbidity (e.g. attention-deficit hyperactivity disorder, depression) or an alternative diagnosis (e.g. specific language impairment) as far as their expertise allows
Person making referral for further assessment should:
  • include all relevant information regarding any concerns, the child/young person’s current situation and details of any professionals involved
  • explain the patient/parent’s understanding of the reason for referral
  • consider providing patient/parent with a copy of the referral letter
  • initiate general management/behaviour strategies and family support in the interim, if necessary by involving multiagency colleagues
The specialist team receiving the referral should:
  • ensure child/young person and parents receive information about the process that will follow referral, including likely timescale of any pre-assessment and assessment phases, and who will be involved
  • if corresponding with professional colleagues to arrange assessments, consider copying correspondence to families
  • inform the parent/carer that they are welcome to bring a supporter if they wish
  • explain that, if any part of the assessment is to be video recorded, the team will obtain written consent of the patient and/or carer (as appropriate) to retain the recording
Please refer to SIGN 98 for the full version of the checklist7
Adapted from Assessment, diagnosis and clinical interventions for children and young people with autism spectrum disorders by kind permission of SIGN

Overcoming practical hurdles to implementation

A drawback with all ASD guidelines that have been published so far6,13–15 is that they have not been allocated specific government funding.4 Nevertheless, the SIGN guideline has identified several areas that have specific resource implications, some of which may have implications for primary care. Health service managers should assess possible cost benefits to be derived from modest training and equipment funding, that could substantially improve ASD services and reduce the stressful, often frustrating, journey currently encountered by many patients, families (and referrers).


The SIGN guideline succeeds in clarifying the evidence on best practice for ASD assessment, investigation, and interventions—non-pharmacological and pharmacological—for UK clinicians and others who are dealing with this disorder. If the advice contained in the guideline is properly implemented by PCTs and health boards, a highly vulnerable group of patients should begin to benefit from improved evidence-based management.

The guideline has also further consolidated our understanding of the evidence surrounding recognition and surveillance of ASD, and has made recommendations about service provision and appropriate levels of information and support. It will assist primary healthcare professionals with improved detection of warning signs for ASD, and when to refer for specialist assessment. It will also improve awareness of what patients and families are entitled to expect from specialist services.

All GPs and their primary care colleagues, in collaboration with specialist professionals, will now be able to mediate for their patients with funding bodies on a more informed basis and explain the pressing case for improvements in ASD resources, audit, and research.


  • ASD have an incidence of approximately 1% in children aged 9–10 years
  • Case finding is best done through the child development programme
  • Diagnosis should be confirmed by referral to a specialist
  • Pharmacological intervention should be initiated and supervised by a specialist
  • Specialist referrals for autism spectrum disorders are not covered by the tariff as they fall under mental health services
  • Paediatric outpatient services1 = £217 (new), £114 (follow-up)
  1. Baird G, Simonoff E, Pickles A et al. Prevalence of disorders of the autism spectrum in a population cohort of children in South Thames: the Special Needs Autism Project (SNAP). Lancet 2006; 368 (9531): 210–215.
  2. Järbrink K, Knapp M. The economic impact of autism in Britain. Autism 2001; 5 (1) 7–22.
  3. MacKay T, Dunlop A-W. The Development of a National Training Framework for Autistic Spectrum Disorders: A Study of Training for Professionals Working in the Field of ASD in Scotland. London: The National Autistic Society; 2004.
  4. McClure I, Le Couteur A. Evidence-based approaches to autism spectrum disorders. Child Care Health Dev 2007; 33 (5): 509–512.
  5. Public Health Institute of Scotland. Autistic spectrum disorders: needs assessment report. Glasgow: PHIS, 2001. Also available online from
  6. Le Couteur A. National Initiative for Autism: Screening and Assessment (NIASA). National Autism Plan for Children (NAPC): Plan for the identification, assessment, diagnosis and access to early interventions for pre-school and primary school aged children with autism spectrum disorder. London: National Autistic Society; 2003.
  7. Scottish Intercollegiate Guidelines Network. Assessment, diagnosis and clinical interventions for children and young people with autism spectrum disorders: a national clinical guideline (SIGN 98). Edinburgh: SIGN, 2007.
  8. Hall D, Elliman D. Health for all children. 4th edition. Oxford: Oxford University Press, 2003.
  9. Scottish Executive. Health for all Children 4: Guidance on Implementation in Scotland 2005. Edinburgh: Scottish Executive; 2005.
  10. Baron-Cohen S, Wheelwright S, Cox A et al. Early identification of autism by the CHecklist for Autism in Toddlers (CHAT). J R Soc Med 2000; 93 (10): 521–525.
  11. Baird G, Charman T, Baron-Cohen S et al. A screening instrument for autism at 18 months of age: a 6-year follow-up study. J Am Acad Child Adolesc Psychiatry 2000; 39 (6): 694–702.
  12. Robins D, Fein D, Barton M, Green J. The Modified Checklist for Autism in Toddlers: an initial study investigating the early detection of autism and pervasive developmental disorders. J Autism Dev Disord 2001; 31 (2): 131–144.
  13. New York State Department of Health, Early Intervention Program. Clinical practice guideline: autism/pervasive developmental disorders: assessment and intervention for young children (Age 0–3 years). New York: New York State Department of Health, 1999.
  14. Volkmar F, Cook E Jr, Pomeroy J et al. Practice parameters for the assessment and treatment of children, adolescents, and adults with autism and other pervasive developmental disorders. American Academy of Child and Adolescent Psychiatry Working Group on Quality Issues. J Am Acad Child Adolesc Psychiat 1999; 38 (12 Suppl): 32S–54S.
  15. Filipek P, Accardo P, Ashwal S et al. Practice parameter: screening and diagnosis of autism. Report of the Quality Standards Subcommittee of the American Academy of Neurology and the Child Neurology Society. Neurology 2000; 55 (4): 468–479G