Implementing an early detection program for autism in primary healthcare: Screening, education of healthcare professionals, referrals for diagnostic evaluation, and early intervention
Introduction
Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by impairments in social interaction, communication, and restricted and stereotyped interests or behaviors (American Psychiatric Association., 2013; World Health Organization., 1992). A report of the global prevalence estimate of ASD indicates an increase over time (Elsabbagh et al., 2012), a trend that started in the late 1980s (McDonald & Paul, 2010). In Iceland, the prevalence was estimated to be 1.2 % in school-aged children born between 1994 and 1998 (Saemundsen, Magnusson, Georgsdottir, Egilsson, & Rafnsson, 2013), and it has more recently been found to be 2.7 % in children born between 2006 and 2008 (Delobel-Ayoub et al., 2020). This new estimate falls within the range of that reported for a similar age group in a recent study in the United States (Baio et al., 2018).
The symptoms of ASD usually manifest in infancy or early childhood. Development appears to be generally intact for the first 6 months of life in children later diagnosed with ASD (Ozonoff et al., 2010; Zwaigenbaum, Bryson, & Garon, 2013). However, prospective studies have found evidence of prodromal symptoms by 6 months of age (Canu et al., 2020; Yirmiya & Charman, 2010). Symptoms in the core social-communication domains of ASD are observable by 12 months in some children, but they usually become pronounced between 14 and 24 months and continue diverging from normal development throughout the third year (Jones, Gliga, Bedford, Charman, & Johnson, 2014; Landa, Gross, Stuart, & Faherty, 2013). Other children attain developmental milestones that are then followed by a developmental plateau or by loss of skills during the second year of life (Landa et al., 2013; Pearson, Charman, Happe, Bolton, & McEwen, 2018).
A reliable diagnosis can be made in children as young as 2–3 years of age (Chawarska, Klin, Paul, & Volkmar, 2007; Landa, 2008). However, considerable time often elapses between the initial concerns and the formal diagnosis of ASD. The median age of ASD diagnosis was 66 months in an Icelandic study, despite early parental concerns (Jónsdóttir, Saemundsen, Antonsdóttir, Sigurdardóttir, & Ólason, 2011). A review of 42 studies found that the median age at diagnosis for ASD ranged from 36 to 82 months. Among the factors associated with age at diagnosis were symptom severity, socioeconomic status, interaction with the service system, and study methods (Daniels & Mandell, 2013). More recent studies report a median age at ASD diagnosis of 52 and 55 months, indicating that there is still need for improvement in terms of earlier detection and diagnosis (Baio et al., 2018; Brett, Warnell, McConachie, & Parr, 2016).
There is evidence that early detection and intervention is advantageous for children with ASD (Estes et al., 2015; MacDonald, Parry-Cruwys, Dupere, & Ahearn, 2014, Zwaigenbaum et al. 2015a). Children diagnosed after they start elementary school have already missed the opportunity to benefit from intervention during their early years, when brain plasticity is at its optimum level (Dawson, 2008; Pierce, Courchesne, & Bacon, 2016). Delayed diagnosis may also result in increased burden and cost for families and communities with respect to long-term care for individuals with ASD (Baxter et al., 2015; Buescher, Cidav, Knapp, & Mandell, 2014). Considering the rising prevalence of ASD, the delay in diagnosis for many children, and the burden of the condition, ASD is a public health concern that calls for preventive actions.
There has been an increased effort to screen for ASD in young children with the aim of enhancing early detection and intervention. The American Academy of Pediatrics (AAP) added weight to this initiative with its recommendation that all children be screened with an ASD-specific tool at 18 and 24 months of age, in addition to general developmental surveillance and screening (Johnson, Myers, & the Council on Children with Disabilities, 2007). Although screening studies have demonstrated effectiveness in detecting young children with ASD (Daniels, Halladay, Shih, Elder, & Dawson, 2014; Zwaigenbaum et al., 2013), the adoption of population-based or universal screening has been a subject of debate (Al-Qabandi, Gorter, & Rosenbaum, 2011). This debate escalated when the US Preventive Services Task Force (USPSTF) issued a report in 2016 stating that there is insufficient evidence to recommend for or against universal screening for ASD in children aged 18–30 months. Of particular concern was the lack of studies on the long-term outcomes of children who have been detected through screening. However, the report did find evidence for valid screening instruments for the above age group and evidence that early intervention has positive effects on the prognosis for children with ASD (McPheeters et al., 2016; Siu et al., 2016).
Many investigators in this field have responded to the USPSTF report by expressing concerns and providing empirical evidence against withholding universal screening for ASD while waiting for more research to be carried out. Among their arguments is that early universal screening is more effective in identifying children with ASD than are parental or physician concerns, resulting in a lowered average age of diagnosis and earlier access to intervention (Coury, 2015; Dawson, 2016; Fein, 2016; Mandell & Mandy, 2015; Pierce et al., 2016; Robins et al., 2016). The USPSTF assumption that children for whom no concerns have been raised and are thus targeted for universal screening are less symptomatic than other children with ASD has been refuted (Coury, 2015; Pierce et al., 2016), and their assumption that intervention studies have not included screened children has been questioned (Fein, 2016; Mandell & Mandy, 2015). Moreover, screening has the potential to reduce social inequalities in age at diagnosis and access to services (Coury, 2015; Dawson, 2016; Fein, 2016; Mandell & Mandy, 2015; Robins et al., 2016). Although it can be argued that scientific evidence supports universal screening for ASD, such screening is not warranted if other services are not readily available for children who screen positive and their families (Fein, 2016; Mandell & Mandy, 2015; Pierce et al., 2016). Thus, studies on the efficacy of screening should include several links in a process chain that also includes diagnostic evaluation, intervention, and the clinical outcomes that result from these services (Silverstein & Radesky, 2016).
In Iceland, there exists a standard procedure for developmental surveillance. This procedure consists of regular well-child visits in public primary healthcare centers for the first four years of life. The developmental surveillance is assisted by the use of broadband developmental screening tests. Prior to this study, there had been no attempts at systematic screening for ASD in Iceland. As soon as professionals in the primary services become aware of signs that may indicate impairment, they have a legal obligation to inform the parents and to take measures in collaboration with the family to refer the child to early intervention and assessment at a secondary service level. Thus, in terms of intervention, the child is given the benefit of the doubt before diagnostic results are available. Early intervention on a daily basis is provided in preschools. The number of hours provided in special education before diagnosis is confirmed is tentative and can vary based on the child’s needs and community regulations. Some children are referred to private practitioners for additional services such as speech and language therapy and physiotherapy. If the initial assessment indicates a neurodevelopmental disability, the child is then referred to a tertiary institution for diagnostic assessment. During the diagnostic process, the child’s needs for intervention are reassessed, both in terms of intensity and teaching methods in the preschool, and the need for additional services. A diagnosis of ASD always leads to a recommendation to use ASD-specific evidence-based intervention methods, if the use of such methods has not already been initiated to some degree. The diagnosis may also result in increased hours in special education. Since universal screening for ASD has the potential to lower the age at diagnosis, it may benefit children in Iceland by providing them with earlier access to more specific and intensive evidence-based interventions. This is crucial, since age at the start of intervention has been linked to outcomes in core behavioral and skill deficits related to ASD (Fuller & amp, 2019).
The Modified Checklist for Autism in Toddlers (M-CHAT; Robins, Fein, Barton, & Green, 2001) and the Modified Checklist for Autism in Toddlers, Revised with Follow-up (M-CHAT-R/F; Robins et al., 2014) are the screening instruments that have been most widely studied and adopted in primary healthcare. The M-CHAT is a brief questionnaire for parents, and a follow-up interview has been developed to reduce a relatively high false positive rate (Kleinman et al., 2008; Robins et al., 2001). A large validation study in the United States of the revised version, the M-CHAT-R/F, found that the instrument significantly reduced the initial screen-positive rate, increased the detection rate for ASD, and lowered the age of ASD diagnosis by 2 years compared with recent surveillance findings (Robins et al., 2014). These instruments have demonstrated the strongest evidence according to the USPSTF (McPheeters et al., 2016).
Population-based screening studies that have used the M-CHAT-R/F have reported sensitivity and specificity above 70 %–80 % (Guo et al., 2019; Magan-Maganto et al., 2018; Robins et al., 2014), which has been estimated to be acceptable for developmental screening instruments (Charman & Gotham, 2013). Less encouraging results have also been reported in large-scale population-based studies using the M-CHAT and the M-CHAT/R, where sensitivity was as low as 34.1 % (Stenberg et al., 2014) and 38.9 % (Guthrie et al., 2019). Children with ASD who are missed by a screen may experience delays in receiving services. Indeed, Guthrie et al. (2019) found that the mean time to diagnosis was 7.5 months shorter for children with ASD who screened positive than for those who screened negative. Given the importance of detecting children with ASD and initiating intervention at the earliest possible age, screening efforts require instruments with relatively high sensitivity in order to minimize false negative cases. Reports of low screening accuracy may undermine the feasibility of universal screening for ASD. However, as has been mentioned above, there are strong arguments for continuing universal screening in primary care while research continues to fill in the gaps where evidence or improvement is still needed. In fact, as noted by Zwaigenbaum and Maguire (2019), “the potential added value of ASD screening must be considered relative to what would happen in its absence” (p. 2).
Improving the early detection of ASD also involves other activities, such as increasing awareness among parents and professionals of developmental milestones and early signs of ASD. Some awareness studies have focused on the education and training of primary healthcare professionals (Daniels et al., 2014; Major, Peacock, Ruben, Thomas, & Weitzman, 2013). This is an important undertaking, since surveys have shown that these professionals’ knowledge of ASD and self-perceived competence in providing primary care to children with ASD are inadequate (Golnik, Ireland, & Borowsky, 2009; Heidgerken, Geffken, Modi, & Frakey, 2005; Will, Barnfather, & Lesley, 2013). Among the variables that have been found to be associated with primary care physicians’ knowledge in this field is continuing medical education on ASD (McCormack, Dillon, Healy, Walsh, & Lydon, 2019). There are limited opportunities available in Iceland for professional development related to ASD for those who work in primary healthcare. For instance, the State Diagnostic and Counseling Center (SDCC) provides regular one- to three-day courses on ASD and teaching methods and holds occasional conferences on the subject, but other opportunities are lacking. A review of the literature indicates that effective educational approaches to improve knowledge for these professionals exist. Such approaches have used a variety of teaching methods, including lectures, case studies, workshop training, and videos (McCormack et al., 2019). When developing a course for primary healthcare professionals, who collaborated with us in this study, we sought inspiration from the Autism Case Training (ACT): A Developmental-Behavioral Pediatrics Curriculum (Centers for Disease Control & Prevention., 2016). Findings from the study of Major et al. (2013) indicate that the ACT curriculum was well received and was associated with increased short-term knowledge and increased self-perceived competence in communicating with families about ASD.
The results of ASD early detection studies in one country may not be generalizable to other countries. Not only does the organization of primary healthcare systems and practices vary, but the variations in awareness and knowledge of ASD and population and cultural characteristics may also play a role. No information is available on the potential benefits of adding screening for ASD to the developmental surveillance program in Iceland or on the knowledge of ASD among well-child care professionals. This is the first part of a prospective study that aims to address this gap in the literature by attempting to increase the knowledge base on early detection of ASD in Iceland. The aim is to study the implementation of an early detection program for ASD within well-child care in primary healthcare centers (PHCs) and to evaluate its initial outcome. The research questions of the present study are as follows: (1) What is the length of time from screening positive to diagnostic confirmation? (2) Will screening for ASD with the M-CHAT-R/F detect and refer more children with the condition than does the usual developmental surveillance? (3) How do well-child care professionals assess their knowledge of ASD and confidence in detecting indications of ASD when using a retrospective pre-test and post-test method? (4) How will screening for ASD be rated by nurses in well-child care who were contact persons between the PHCs and the study? (5) What is the rate of parental participation in the screening and use of psychological services after participation? (6) What is the length of time from screening positive to the start of intervention?
Section snippets
Setting
Iceland’s population was 343,000 during the period of study, with just over 4000 live births per year (Statistics Iceland, 2020a). The healthcare system is state-run and covers the whole country. There are public PHCs throughout the country that offer a broad range of primary care services, including well-child care and immunizations. Parents are free to choose to obtain services at any PHC they want, whether or not they are registered there. Besides the free services of the PHCs, parents can
Attendance and participation rates
A total of 2531 children born at the target age of the study were registered at the participating PHCs. Of these children, 2201 (87 %) came for their 30-month visit, and of those, 1586 (72.1 %) agreed to participate in the study; these participants constituted 62.7 % of the total target population. The participation rates in the ASD screening among the PHCs ranged from 51.7 %–95.2 %. The difference in number between those attending the 30-month visit (2201) and those participating in the ASD
Discussion
This study presents the initial results of an early detection program for ASD in primary healthcare in Iceland. It included screening with the M-CHAT-R/F in connection with regular developmental surveillance of 1586 children at 30 months of age in nine randomly selected PHCs, an educational course on ASD for well-child care professionals, and referrals for diagnostic evaluation and intervention. More children in the study sample were detected and referred with indications of ASD based on the
Conclusion
The study shows that it is clinically feasible to implement screening for ASD with the M-CHAT-R into well-child care in Iceland. The M-CHAT-R/F detected some children with ASD who were missed by the usual developmental surveillance at 30 months of age. Identification of possible false negative cases awaits a follow-up of the participants after their next well-child visit at 48 months of age. The availability of services for screen-positive children contributed to the success of the early
CRediT authorship contribution statement
All authors participated in designing the study. SLJ coordinated the project, collected and analyzed the data and wrote the first draft of the manuscript. All co-authors revised the manuscript and approved the final version.
Declaration of Competing Interest
The authors have no conflict of interest to declare.
Acknowledgements
The study received funding from the Ministry of Social Welfare (VEL15100238), the SDCC’s Memorial Fund, the Barnavinafelagid Sumargjof Fund, and the Oddur Olafsson Memorial Fund. We thank the PHC directorate for their support and the families and professionals at the participating centers for their collaboration.
References (84)
- et al.
Approaches to enhancing the early detection of autism spectrum disorders: A systematic review of the literature
Journal of the American Academy of Child and Adolescent Psychiatry
(2014) - et al.
Long-term outcomes of early intervention in 6-year-old children with autism spectrum disorder
Journal of the American Academy of Child and Adolescent Psychiatry
(2015) - et al.
Developmental pathways to autism: A review of prospective studies of infants at risk
Neuroscience and Biobehavioral Reviews
(2014) - et al.
Children diagnosed with autism spectrum disorder before or after the age of 6 years
Research in Autism Spectrum Disorders
(2011) - et al.
A comparison of three retrospective self-reporting methods of measuring change in instructional practice
The American Journal of Evaluation
(2003) - et al.
Assessing progress and outcome of early intensive behavioral intervention for toddlers with autism
Research in Developmental Disabilities
(2014) - et al.
A new screening programme for autism in a general population of Swedish toddlers
Research in Developmental Disabilities
(2012) - et al.
To screen or not to screen universally for autism is not the question: Why the task force got it wrong
Jornal de Pediatria
(2016) - et al.
Barriers faced by immigrant families of children with autism: A program to address the challenges
Asian Journal of Psychiatry
(2019) - et al.
Early identification of autism spectrum disorders
Behavioural Brain Research
(2013)
Early autism detection: Are we ready for routine screening?
Pediatrics
Diagnostic and statistical manual of mental disorders
Prevalence of autism spectrum disorder among children aged 8 years - Autism and developmental disabilities monitoring network, 11 sites, United States, 2014
MMWR Surveillance Summaries
Screening young children for autism spectrum disorders in primary practice
Journal of Autism and Developmental Disorders
The epidemiology and global burden of autism spectrum disorders
Psychological Medicine
Correction to: Early detection, diagnosis and intervention services for young children with autism spectrum disorder in the European Union (ASDEU): Family and professional perspectives
Journal of Autism and Developmental Disorders
Use of the modified checklist for autism, revised with follow up-Albanian to screen for ASD in Albania
Journal of Autism and Developmental Disorders
Factors affecting age at ASD diagnosis in UK: No evidence that diagnosis age has decreased between 2004 and 2014
Journal of Autism and Developmental Disorders
BRIGANCE þroskaskimun fyrir 2½ árs börn, EPS II [BRIGANCE, early preschool screen II]
Reykjavík: Embætti landlæknis, Þróunarsvið og Þroska- og hegðunarstöð Heilsugæslu
Implementing systems-based innovations to improve access to early screening, diagnosis, and treatment services for children with autism spectrum disorder: An autism spectrum disorder pediatric, early detection, engagement, and services network study
Autism
Costs of autism spectrum disorders in the United Kingdom and the United States
JAMA Pediatrics
Early non-social behavioural indicators of autism spectrum disorder (ASD) in siblings at elevated likelihood for ASD: A systematic review
European Child and Adolescent Psychiatry
Improving early identification and ongoing care of children with autism spectrum disorder
Pediatrics
Autism case training: A developmental-behavioral pediatrics curriculum
Measurement Issues: Screening and diagnostic instruments for autism spectrum disorders - lessons from research and practice
Child and Adolescent Mental Health
Erratum to: Behavior change interventions and policies influencing primary healthcare professionals’ practice-an overview of reviews
Implementation Science
Autism spectrum disorder in the second year: Stability and change in syndrome expression
Journal of Child Psychology and Psychiatry, and Allied Disciplines
Babies, bathwater, and screening for autism spectrum disorder: Comments on the USPSTF recommendations for autism spectrum disorder screening
Journal of Developmental & Behavioral Pediatrics
Explaining differences in age at autism spectrum disorder diagnosis: A critical review
Autism
Early behavioral intervention, brain plasticity, and the prevention of autism spectrum disorder
Development and Psychopathology
Why it’s important to continue universal autism screening while research fully examines its impact
JAMA Pediatrics
Prevalence of autism spectrum disorder in 7-9-year-old children in Denmark, Finland, France and Iceland: A population-based registries approach within the ASDEU project
Journal of Autism and Developmental Disorders
Autism spectrum disorder screening and management practices among general pediatric providers
Journal of Developmental & Behavioral Pediatrics
Global prevalence of autism and other pervasive developmental disorders
Autism Research
Commentary on USPSTF final statement on universal screening for autism
Journal of Developmental & Behavioral Pediatrics
The effects of early intervention on social communication outcomes for children with autism spectrum disorder: A meta-analysis
Journal of Autism and Developmental Disorders
Identifying autism in a brief observation
Pediatrics
Screening for autism spectrum disorders: State of the art in Europe
European Child & Adolescent Psychiatry
PEDS Mat foreldra á þroska barna [Parents’ Evaluation of Developmental Status]
Reykjavík: Námsmatsstofnun og Landlæknisembættið
Medical homes for children with autism: A physician survey
Pediatrics
Diffusion of innovations in service organizations: Systematic review and recommendations
The Milbank Quarterly
Reliability and validity of the chinese version of modified checklist for autism in toddlers, revised, with follow-up (M-CHAT-R/F)
Journal of Autism and Developmental Disorders
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