Testing a Cognitive Behavioural Therapy Program for Anxiety in Teenagers on the Autism Spectrum: A Feasibility Study
Phase: NA
Conditions: Anxiety, Autism
Sponsor: University of Aarhus

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PROTOKOL 
 
 
 
 
Testing a Cognitive Behavioural Therapy program for  
Anxiety in Teenagers on the Autism Spectrum: 
A feasibility study 
 
 
 
 
Tina R. Kilburn, Psychologist, PhD 1 
Project leader (PI) 
Ronald M. Rapee, Professor 2 
Heidi Lyneham, Clinic Director 2 
Mikael Thastum3 
Per Hove Thomsen, MD, DrMedSci 1 
 
 
1 Centre of Child and Adolescent Psychiatry, Aarhus University Hospital, Denmark 
2 Centre for Emotional Health, Department of Psychology, Macquarie University, Sydney, Australia 
3 Centre for the Psychological Treatment of Children and Adolescents (CEBU), Department of 
Psychology and Behavioral Science, Aarhus University, Denmark 
 
 
 
 

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Objectives 
The primary objective is to investigate the feasibility of a newly developed manualised group 
Cognitive Behavioural Therapy (CBT) programme for anxiety in teenagers (aged 13-17 years) with 
Autism Spectrum Disorder (ASD). Our aim is to focus primarily on acceptability and compliance with 
the program with some investigation of treatment effects on anxiety diagnosis and anxiety 
symptoms. 
 
Background 
Autism spectrum disorders (ASD) include deviations and delays in the development of social 
interaction, communication patterns, restricted stereotyped and repetitive behaviours, and areas of 
interests (Szatmari, 2003). ASD conveys persisting negative effects on learning and development of 
independence in adulthood (Howlin, Goode, Hutton, & Rutter, 2004).  
 
The prevalence of ASD has increased markedly over the last three decades (Atladottir 
et al., 2015; Bertrand et al., 2001; Fombonne, 2002; Scott, Baron-Cohen, Bolton, & Brayne, 2002; 
Wing & Potter, 2002) and is now thought to occur in about 6 cases per 1000. The average age of 
diagnosis is around 5.3 years (Parner, Schendel, & Thorsen, 2008) but resent studies show a large 
increase in incidence rates for ASD among teenagers (Jensen, Steinhausen, & Lauritsen, 2014). This 
increase is mainly identified for Asperger’s syndrome since higher functioning children and teenagers 
with ASD are harder to identify before the beginning of adolescence where demands on social 
communication skills, flexibility and social interaction become more complex and thus surpass the 
ability of the young adult (Jensen et al., 2014). 
 
Approximately half of teenagers diagnosed with ASD have a relatively poor psychosocial 
development into adulthood (Eaves & Ho, 2008) affecting work prospects, friendships and 
independence, and leaving them socially isolated and reliant on social, community and family care 
(Schall, Wehman, & Carr, 2014). Although outcome for adults with ASD has improved over recent 
years, many remain highly dependent on others for support (Howlin et al., 2004).  
 
Co-morbid disorders in Individuals with ASD are common (Coleman, 2000; Ghaziuddin, 
2005) and seem to have an even greater impact on the young person’s life than the ASD itself 
(Coleman, 2000; Gillberg & Coleman, 1992). Thus, treatment of co-morbid disorders may potentially 
add considerably to the improvement of quality of life, general functioning, independence and 
development (Ghaziuddin, 2005). 
 
Anxiety disorders (Brereton, Tonge, & Einfeld, 2006; Leyfer et al., 2006; Simonoff et al., 

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2008; Steinhausen & Metzke, 2004) are some of the most prominent co-morbid disorders and are 
estimated to occur in 11-84% of individuals with ASD (Kreslins, Robertson, & Melville, 2015). Due to 
a unique interaction between anxiety and core ASD symptomology, the manifestation of anxiety in 
individuals with ASD differs in several ways from anxiety seen in typical developing youths. Anxiety 
in ASD is associated with more behavioural problems, such as social avoidance, repetitive behaviours 
and aggression (Kreslins et al., 2015). 
 
Cognitive Behavioural Therapy (CBT) is shown to be very effective in the treatment of 
anxiety in neuro-typical children and teenagers (Higa-McMillan, Francis, Rith-Najarian, & Chorpita, 
2016; Reynolds, Wilson, Austin, & Hooper, 2012).  Children with co-morbid ASD, however, seem to 
respond less favourably to standard CBT programs (Rapee, 2003) and research shows that CBT 
programs specifically designed for children with ASD and co-morbid anxiety are highly efficacious in 
treating anxiety disorder (Chalfant, Rapee, & Carroll, 2007; Kilburn et al., 2020; Kreslins et al., 2015; 
Storch, Arnold, & Lewin, 2013; Sukhodolsky, Bloch, Panza, & Reichow, 2013) thereby reducing the 
co-morbid symptoms that otherwise untreated may lead to extra impairment in daily life skills. The 
majority of this evidence, however, is from studies with younger children and, to our knowledge, no 
study has so far evaluated the efficacy of such a program specifically developed for teenagers 
(Perihan et al., 2019).  
 
Treatment of anxiety in teenagers with ASD is especially important since this is a 
vulnerable time of development. The teenage years are when social relationships become most 
important, youngsters start dating and get sexually interested, become more independent, and ideas 
and motivations are forming for future careers and work (Rapee et al., 2019). Autism Spectrum 
Disorder and co-morbid anxiety will interfere with many of these processes making this co-morbidity 
during the teenage period especially critical for long-term functioning, independence and ability to 
become self-sufficient (Volkmar, Reichow, & McPartland, 2014).  
 
The CBT program aimed at younger children between 7 and 13 years of age – ‘Cool Kids 
ASD Anxiety Program’ 2nd Ed. (Lyneham, Chalfant, Kilburn, & Rapee, 2018 (in print)) – has been 
examined in a randomized controlled trial (RCT) in a non-English-speaking general hospital setting. 
The study showed positive results in the efficacy and satisfaction of the program for younger children 
with ASD and anxiety (Kilburn et al., 2020). However, this program is not suitable for teenagers above 
the age of 12-13 years and thus, the efficacy on older teenagers and young adults are uncertain. 
 
The child version – ‘Cool Kids ASD Anxiety Program’ 2nd Ed. (Lyneham et al., 2018 (in 
print)) – uses hand puppets and animal cartoons and relates on full parental support. Issues dealt 

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with concerns mainly topics related to young children and the challenges they might face on a daily 
basis.  
 
A program for older teenagers and young adults needs to target topics related to this 
age group where specific age-related challenges associated with this group of young people with ASD 
can be incorporated. Since social relationships are a main challenge for many young people with ASD 
and often courses them to withdraw from others and experience levels of social anxiety (Rapee et 
al., 2019), topics related to overcoming social difficulties and solving problems without close parental 
assistant are important to target in such a program. Further, targeting the co-morbid anxiety needs 
to be approached in an age-related manor in order to enhance involvement and participation in the 
program. 
 
Since high functioning ASD is often not recognised before adolescence, the co-morbid 
difficulties might not have been dealt with earlier leaving these teenagers in need of disorder- and 
age-appropriate treatment programs. Thus, in order to secure the best possible developmental paths 
and future possibilities for teenagers with ASD, it is important that age-appropriate treatment 
manuals aimed at co-morbidities such as anxiety are developed and tested. 
 
Method/Design 
In cooperation with professor Ronald Rapee and clinic director Heidi Lyneham (the developers of the 
original Cool Kids programs) (Lyneham, Abbott, Wignall, & Rapee, 2003), we have developed an age-
appropriate version of a manualised CBT group treatment suited to treat teenagers with ASD and co-
morbid anxiety.  
 
The program is in the process of being edited and finalised before translation and 
adaptation to Danish conditions. 
 
Development of ‘Chilled ASD Anxiety Program’ 
The ‘Cool Kids ASD Anxiety Program’ was developed at the Centre for Emotional Health, Macquarie 
University, Australia specifically for children with ASD and co-morbid anxiety allowing for the 
difficulties that children with ASD experience (Lyneham et al., 2018 (in print)). The ‘Cool Kids ASD 
Anxiety Program’ is aimed at children aged between 6 and 13 years and follows the original ‘Cool Kids 
Anxiety Program’ (Lyneham et al., 2003) but with modifications relevant to autism. The cognitive 
work has been simplified, 2 relaxation techniques are introduced and in-session exposure is part of 
the planning together with simplification of the material with many prepared worksheets and 

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pictures. Further, two hand puppets are introduced in order to visualise and externalise the anxiety 
issues. 
 
Using the child version of the ASD program as a template and some of the approaches 
in the ‘Cool Kids (Chilled) Adolescent Anxiety Program’ program for neuro-typical teenagers, the PI 
Tina R. Kilburn has in collaboration with the Centre for Emotional Health, Macquarie University, 
Australia developed a version (‘Chilled ASD Anxiety Program’ (working title)) aimed at individuals 
above 13 years of age with ASD and co-morbid anxiety disorder. Further, in the development of the 
‘Chilled ASD Anxiety Program’ specific age-challenges (e.g. social difficulties, building confidence, 
problem solving ect.) associated with this group of young people with ASD have been incorporated. 
After joint editing and finalisation of the program it will be translated into Danish before being tried 
in the feasibility study. 
 
 
Procedure 
Study population 
Thirty teenagers aged 13-17 years with an active ASD diagnosis and experiencing life interference 
anxiety symptoms will be eligible to participate in the study. Even though we expect the program to 
be beneficial for individuals older than 17 it will be more appropriate to recruit youngsters under the 
age of 18 (the legal age in Denmark) to enhance parents' participation. 
 
Visitation 
Recruitment will take place through information conveyed to general practitioners, different 
Regional Centres of Child and Adolescent Psychiatry, Community Care offices, the ASD association, 
and through media such as newspapers, journals and the internet.  
After first contact the families will be contacted by the PI via email with the written information 
informing them about the project, the inclusion and exclusion criteria together with an invitation to 
a personal meeting conducted at a private interviewing room at the Aarhus University Hospital, 
Psychiatry, Department of Child and Adolescent Psychiatry, Research Unit or at the 'Joint 
Counselling for Children and Youths' (PPR) in Frederiksberg. In the mail and in the written 
information the right to bring an assessor at the meeting is explained. At the meeting, informal 
clinical screening of anxiety symptoms will be performed by way of interviewing the family about 
their daily life and experienced challenges, further information will be given and consent form 
signed by both parents with joint custody. If the young participant becomes of age (turns 18 years) 

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during the project time, he/she will have to sign a new personal consent form. The family is entitled 
to 48 hours reflection time before signing the concentform. Clinical psychologist with extensive 
knowledge of the project, ASD and anxiety will convey the oral information. The young people 
participating in the trial will receive the same oral information and be involved in the conversations 
with the parents about the trial. The young person's own statements will be given crucial 
importance. 
 
The participants will receive a small token of gratitude in the form of a trip to the cinema 
for the family (DKK 500,-) for completing the treatment and answering all interviews and 
questionnaires throughout the project. 
 
 
Inclusion  
To be considered for enrolment into the project the teenagers will have to fulfil the diagnostic criteria 
for one or more anxiety diagnoses on the Anxiety Disorders Interview Schedule for DSM-IV: Parent & 
Child interview schedule (ADIS C/P) (Silverman & Albano 1996). 
 
Further, a diagnosis of ASD according to the International Classification of Diseases, 
10th edition (ICD 10) (WHO, 2010) by a Private Psychiatric Clinic or by one of the Regional Child and 
Adolescent Psychiatric Centres in Denmark should have been obtained. The ASD diagnosis may not 
later have been revoked by a psychiatrist. Participants will not be accepted into the project without 
accompanying documentation of their ASD diagnosis.  
 
Exclusion 
Exclusion criteria for entering the trial is low intellectual functioning (<70). Assessment of cognitive 
ability (IQ) has often been part of the investigation regarding a possible ASD diagnosis and will, with 
parental consent, be retrieved from the teenager's journal. However, if assessment of IQ is missing a 
short version of the Wechsler Intelligence Scale for Children (Wechsler, 2014) will be performed. 
 
Further exclusion criteria are active psychosis, untreated hyperkinetic disorder, inability 
to speak Danish, or inability to leave the home, attend a group setting, or to meet for treatment 
caused by other psychiatric disorders.  
 
Intervention 
The group based manualised CBT intervention program ‘Chilled ASD Anxiety Program’ (working title) 

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will be used. The program will be conducted in 10 sessions over approximately 13 weeks with a 
further booster session 3 months after treatment. The sessions are group based comprising five 
teenager and parent dyads and conducted weekly, with a one week break after sessions 3, 6, and 8 
to allow participants time to implement strategies in daily life. Each session lasts 2 hours and includes 
time spent working with the teenagers alone, time with the parents alone and time with parents and 
teenagers together. The teenager and at least one parent will attend the groups. The main group 
therapist will be a psychologist certified or well experienced in the Cool Kids programs and the co-
therapist will be a psychiatric nurse, educationalist, or master class or above psychologist. Further, a 
graduate psychologist will be involved as a practical helper. 
 
Treatment integrity will be assed for teenager and parent dyads using questionnaires 
regarding number of sessions attended and homework compliance. All sessions will be videotaped 
and adherence to the manual will be assessed through observation of a random selection of 2 
sessions out of the 10 sessions (20%) for each treatment group by a therapist who has not been 
involved in the treatment.  
 
Participants will be encouraged not to seek other forms of treatment or change possible 
psychopharmacological medication during the trial period. 
 
Measures 
Feasibility 
Post-treatment teenagers and parents will be asked to complete a questionnaire adapted from The 
Experience of Service Questionnaire (Attride-Sterling, 2002; Brown, Ford, Deighton, & Wolpert, 2014) 
measuring their satisfaction with the treatment. On a Likert scale they will be asked to rate positive 
statements as 'not true' (1), 'partly true' (2), or 'true' (3) and in an open section freely comment on 
their experience with the treatment.  
 
Participant dropouts will be investigated together with the proportion of completed 
sessions, homework and questionnaires.  
 
Therapists will complete a qualitative survey regarding satisfaction with contents, ease 
of conveying program, and suitability of the program to teenagers with ASD.  
 
Following completion of the program a focus group comprising a sample of participating 
teens and separately parents will be established to discuss the strengths and weaknesses of the 
program. 

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Anxiety 
Diagnosis of primary anxiety will be carried out using the Anxiety Disorders Interview Schedule for 
DSM-IV: Parent & Child interview schedule (ADIS/CP) (Silverman & Albano, 1996) for both teenagers 
and parents. ADIS/CP is a semi-structured interview with separate interviews for both teenager and 
parents designed to assess for current episodes of anxiety disorders, and to permit differential 
diagnosis among the anxiety disorders according to DSM-IV criteria. 
 
The disorders are rated with a clinical severity rating (CSR) from 0 (no interference) to 
8 (extreme interference) with severity ratings of 4 or above signifying the presence of a clinical 
disorder. The assessor's CSR score will be based on a combination of the parent and teenagers' CSR 
score plus a clinical evaluation of the extent of severity. The disorder with the most impairing 
diagnosis will be considered the primary anxiety diagnosis. 
 
The ADIS/CP has demonstrated good-to-excellent 7–14 days test–retest reliability for 
the presence of specific anxiety diagnoses (Cohen's Kappa [κ] range for different diagnoses = 0.71–
0.84 for children's interviews and 0.73–0.92 for parent's interviews) (Silverman, Saavedra, & Pina, 
2001). 
 
The ADIS/CP assessment will be performed by trained psychology students under 
supervision of a senior assessor. The interviewers will be blinded to the purpose of the study and will 
not assess the same participant more than once. 
 
Additional anxiety assessments administered to teenagers and parents will be collected 
by the following questionnaires using an on-line data collection platform (REDCAP). 
 
Spence Children's Anxiety Scale (SCAS) (Spence, 1998), is a questionnaire for teenagers and parents 
assessing the severity of anxiety symptoms broadly in line with the dimensions of anxiety disorder 
proposed the DSM-IV. 
Children's Anxiety Life Inference Scale (CALIS) (Lyneham et al., 2013), is designed to assess life 
interference attributed to fears and worries from teenager and parent perspectives. The measure 
targets interference with the teenager's life and with the parent's/family's life. 
Children's Automatic Thoughts Scale (CATS) (Schniering & Rapee, 2002), is a developmentally 
sensitive, general measure of negative self-statements across both internalizing and externalizing 
problems. Four separate subscales of cognitive content are assessed including physical threat, social 
threat, personal failure, and hostility.  

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Further, indications of ADHD will be assessed using the Attention Deficit/Hyperactive 
Disorder-Rating Scale (ADHD-RS) (DuPaul, Power, Anastopoulos, & Reid, 1998) and Teenagers' and 
parent’s quality of life will, in addition, be investigated with The WHO-five Well-being Index (WHO-
5) (Bech, 2004). 
 
All measurements will be performed before baseline (Pre), after the intervention (Post) 
and at 3 months follow-up (Fu) (See Fig. 1). 
 
Finally, demographic information will be obtained by questions concerning level of 
education, employment, household income, number of siblings etc. in addition to other background 
data such as previous treatment, special school attendance etc. 
 
Analysis 
This feasibility study is being conducted to assess the feasibility of the project in order to be able to 
scale to a bigger study. Our main aim is to learn about enrolment challenges, satisfaction of manuals 
and delivery of program, questionnaires and interview schedule. With this aim in mind we expect 
that a study population of 30 teenagers is a reasonable sample. 
The satisfaction questionnaires will be analysed by calculating the percentage of 'not true', 'partly 
true', or 'true' answers for each of the questions while examples of both positive and negative 
comments will be reported including reasons for possible dropouts. Percentage of participant 
dropouts will be calculated together with the quantity of completed sessions and questionnaires. 
Extent of homework completed in preparation for each session will be calculated.  Comments from 
therapists' survey and the focus group will be collected and reported as qualitative data. 
 
 Outcomes regarding changes in diagnostic status, severity of anxiety symptoms, life 
interference attributed to fears and worries, and teenagers' negative self-statements measured with 
ADIS/CP, SCAS, CALIS and CATS will be investigated. Mean scores (M) with standard deviations (SD) 
will be calculated Pre and Post-treatment and at FU for the above measurement followed by the use 
of Cohen's d for repeated measures to calculate within-group effect sizes at the different data points 
– pre to post-treatment and post-treatment to FU.  
 
In addition, the overall percentage of teenagers free of primary anxiety disorder and 
free of all anxiety disorders will be calculated. 
  
Statistical analyses will be conducted by the use of STATA (StataCorp, 2019) and the 
significance level will be set at P value of less than 0.05. 
 

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Timeline 
January 2021 – June 2021 
 Final translation and modification of treatment manual for teens, parents and therapists 
 
Request for Research Ethics Committee 
 
Notification to the Data Protection Agency 
 Continuing funds applications 
 Development of information material  
July 2021 – September 2021 
 Training of therapists 
 Interviewing and inclusion of patients 
October 2021 – June 2022 
 Conducting feasibility study with 15 teenagers (see Fig. 1.) 
July 2022 – December 2022 
 Data analysis 
 Publications 
 
Collaborations 
The project is instigated in a collaboration between Aarhus University Hospital, Psychiatry, 
Department of Child and Adolescent Psychiatry, Research Unit and Professor Ronald Rapee and 
clinic director Heidi Lyneham, Centre for Emotional Health, Macquarie University, Sydney, Australia. 
The existing successful cooperation with the Centre for the Psychological Treatment of Children and 
Adolescents (CEBU), Department of Psychology and Behavioural Science, Aarhus University, (Kilburn 
et al., 2020; Kilburn et al., 2018, 2019) is extended by agreement with Professor Mikael Thastum to 
include the above project. 
Part of the intervention (approx. 3 additional groups) will take place at the 'Joint Counselling for 
Children and Youths' (PPR) in Frederiksberg. The recruiting, inclusion and data collection will be as 
described above and the therapist undertaking the treatment will be trained by the PI.  
 
Plan for dissemination 
All results, positive, negative or inconclusive, will be published in international, peer-reviewed 
psychiatric or psychological journals and be presented at relevant international conferences. National 

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interest associations, social medias and national media outlets will be informed together with Danish 
Regions and Local Authorities in order to update knowledge and enhance implementation. If the 
manualised treatment program appears beneficial the material will be available for purchase by 
professionals at CEBU, Department of Psychology and Behavioural Science, Aarhus University 
containing the names of the funding contributors.  
 
Legal and financial aspects 
Macquarie University will have copyright of the program abroad and a license to print and distribute 
the Danish version will be bestowed CEBU, Department of Psychology and Behavioural Science, 
Aarhus University who holds the sole Danish rights to other Danish Cool Kids treatment versions.  
The study is funded by the TRYG Foundation with 999.664 DKK over a 2-year period. The funding will 
be used for remuneration of staff, materials, compensation, publication etc. and is payed to and 
administrated by Aarhus University Hospital, Psychiatry, Department of Child and Adolescent 
Psychiatry, Research Unit. The PI or other researches associated with this project have no economic 
affiliation with the TRYG Foundation.      
 
Ethical consideration 
The study is in the process of seeking approval from the relevant regional Ethics Committees. 
In order to limit invasion in the family's lives with additional examinations it is decided to include 
teenagers already diagnosed with ASD.  
 
Some participants might experience slightly elevated anxiety level when initiating the 
program due to confrontation of the problem. Information regarding this phenomenon will be 
offered at the first personal meeting between the family and the PI in order for them to contemplate 
a possible withdrawal from the study. Further, based on clinical judgement referral to relevant post 
trial treatment options will be conducted for non-responding participants (after follow-up).  
The Data Protection Regulation and the Data Protection Act are complied with in connection with the 
processing of personal data in the project. The study is covered by the patient compensation act. 
 
Perspectives 
Resent findings provide evidence for the benefit of manualised CBT programs for children with ASD 
and co-morbid anxiety disorders (Perihan et al., 2019). In order to investigate whether the CBT 
program Cool Kids ASD can be adapted for teenagers, and positive findings regarding the efficacy of 

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the program in children (Chalfant et al., 2007; Kilburn et al., 2020; Kilburn et al., 2019), this study 
aims to determine the feasibility of the ‘Chilled ASD Anxiety Program’.  
 
The literature provides evidence to suggest that structured, intense intervention like a 
manualised CBT group program not only will improve the main presenting difficulty (Danial & Wood, 
2013; Kreslins et al., 2015; Storch et al., 2015; van Steensel & Bogels, 2015), but also other aspects of 
the participant’s functioning such as peer relationships (Hirshfeld-Becker & Biederman, 2002).  
 
Diminishing anxiety symptoms and maybe even symptoms of other co-morbid disorders 
may have great impact on the severity of the ASD and in addition, may aid in improving quality of life 
for the whole family while enhancing the teenager's prospects for independence. 
However, to our knowledge standardized programs designed specifically for teenagers with ASD and 
anxiety are lacking and there are several clinical and practical difficulties in applying child-focussed 
programs in this age-group. In order to provide an efficient treatment, it is thus important to develop 
and investigate a manualised age appropriate program adapted to the specific challenges young 
people with ASD faces in their teenage years. 
 
Manualized CBT manuals like the 'Chilled ASD anxiety program' aimed at teenagers are 
of great need in order to facilitate the transportability of feasibility and efficacy to care settings where 
therapists may have less opportunity for extensive CBT training and expertise development. This, in 
turn, will improve implementation and provide age relevant treatment to a large sample of teenagers 
with ASD enhancing their possibility for future development, education and quality of life. 
 
If results from this study are shown to be as positive as the results from the recently 
finished study investigating the efficacy of the Cool Kids ASD anxiety treatment program for younger 
children in a general hospital setting (Kilburn et al., 2020), a RCT study of this new 'Chilled ASD anxiety 
program' may not be of urgent necessity before being available in clinical practice. However, long-
term and in order to further establish efficacy of the program it will be required to conduct a larger 
RCT study. 
 
Positive outcomes regarding satisfaction of the program for both families and therapists 
will, in addition, support the imminent implementation and use of the program in both child 
psychiatric and community settings even though a RCT is not yet completed.  
 
The regular Cool Kids anxiety program has been tested on Danish children with good 
results (Arendt, Hougaard, & Thastum, 2016) and is now widely used in treatment of anxiety in neuro-
typical children nationwide with CEBU successfully handling the distribution of manuals and courses 
in how to use the program. Subsequent the efficacy study (Kilburn et al., 2020), the Cool Kids ASD 

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anxiety treatment program for younger children is in the beginning of an implementation phase 
where distribution of manuals and access to courses for psychologists nationwide are being planned 
using the same set-up at CEBU. Depending on results from this feasibility study the 'Chilled ASD 
anxiety program' will be administrated using the same established system. 
 
 
 
 
References 
 
Arendt, K. B., Hougaard, E., & Thastum, M. (2016). Efficacy of a Danish version of the Cool Kids program: a randomized 
wait-list controlled trial. Acta Psychiatr Scand, 133(2), 109-121.  
Atladottir, H. O., Gyllenberg, D., Langridge, A., Sandin, S., Hansen, S. N., Leonard, H., . . . Parner, E. T. (2015). The 
increasing prevalence of reported diagnoses of childhood psychiatric disorders: a descriptive multinational 
comparison. Eur Child Adolesc Psychiatry., 24(2), 173-183. doi:10.1007/s00787-014-0553-8. Epub 2014 May 6. 
Attride-Sterling, J. (2002). Development of methods to capture users’ views of CAMHS in clinical governance reviews. 
Retrieved from Cambridge, UK:  
Bech, P. (2004). Measuring the dimension of Psychological General Well-Being by the WHO-5. QoL Newsletter, 32, 15-
16.  
Bertrand, J., Mars, A., Boyle, C., Bove, F., Yeargin-Allsopp, M., & Decoufle, P. (2001). Prevalence of autism in a United 
States population: The Brick Township, New Jersey, investigation. Pediatrics, 108(5), 1155-1161. 
doi:10.1542/peds.108.5.1155 
Brereton, A. V., Tonge, B. J., & Einfeld, S. L. (2006). Psychopathology in children and adolescents with autism compared 
to young people with intellectual disability. Journal of Autism and Developmental Disorders, 36(7), 863-870. 
doi:10.1007/s10803-006-0125-y 
Brown, A., Ford, T., Deighton, J., & Wolpert, M. (2014). Satisfaction in Child and Adolescent Mental Health Services: 
Translating Users Feedback into Measurement. Adm Policy Ment Healt, 41(4), 434-446. doi:10.1007/s10488-
012-0433-9 
Chalfant, A., Rapee, R. M., & Carroll, L. (2007). Treating Anxiety Disorders in Children with High Functioning Autism 
Spectrum Disorders: A Controlled Trial. J Autism Dev Disord, 37(10), 1842-1857.  
Coleman, M. (2000). The biology of the autistic syndromes. Cambridge: University Press. 
Danial, J. T., & Wood, J. J. (2013). Cognitive behavioral therapy for children with autism: review and considerations for 
future research. J Dev Behav Pediatr, 34(9), 702-715. doi:10.1097/DBP.0b013e31829f676c [doi] 
DuPaul, G. J., Power, T. J., Anastopoulos, A. D., & Reid, R. (1998). ADHD Rating Scale—IV: Checklists, norms, and clinical 
interpretation. New York, NY, US: Guilford Press. 
Eaves, L. C., & Ho, H. H. (2008). Young adult outcome of autism spectrum disorders. J Autism Dev Disord, 38(4), 739-
747. doi:10.1007/s10803-007-0441-x 
Fombonne, E. (2002). Epidemiological trends in rates of autism. Mol Neuropsychiatry, 7, S4-S6. 
doi:10.1038/sj.mp.4001162 
Ghaziuddin, M. (2005). Mental health aspects of autism and Asperger syndrome. London, UK: Jessica Kingsley 
Publishers. 
Gillberg, C., & Coleman, M. (1992). The biology of the autistic syndromes. London, UK: Mac Keith Press. 
Higa-McMillan, C. K., Francis, S. E., Rith-Najarian, L., & Chorpita, B. F. (2016). Evidence Base Update: 50 Years of 
Research on Treatment for Child and Adolescent Anxiety. Journal of Clinical Child and Adolescent Psychology, 
45(2), 91-113.  
Hirshfeld-Becker, D. R., & Biederman, J. (2002). Rationale and principles for early intervention with young children at 
risk for anxiety disorders. Clinical child and family psychology review, 5(3), 161-172.  
Howlin, P., Goode, S., Hutton, J., & Rutter, M. (2004). Adult Outcome for Children with Autism. Journal of Child 
Psychology and Psychiatry, 45(2), 212-229. doi:10.1111/j.1469-7610.2004.00215.x 

77812_Protocol_210410_Version 5 
14 
 
Jensen, C. M., Steinhausen, H. C., & Lauritsen, M. B. (2014). Time Trends Over 16 Years in Incidence-Rates of Autism 
Spectrum Disorders Across the Lifespan Based on Nationwide Danish Register Data. Journal of Autism and 
Developmental Disorders, 44, 1808-1818. doi:10.1007/s10803-014-2053-6. 
Kilburn, T. R., Sørensen, M. J., Thastum, M., Rapee, R. M., Rask, C. U., Arendt, K. B., . . . Thomsen, P. H. (2020). Group 
Based Cognitive Behavioural Therapy for Anxiety in Children with Autism Spectrum Disorder: A Randomised 
Controlled Trial in a General Child Psychiatric Hospital Setting. J Autism Dev Disord, [Epub ahead of print]. 
doi:10.1007/s10803-020-04471-x 
Kilburn, T. R., Sørensen, M. J., Thastum, M., Rapee, R. M., Rask, C. U., Arendt, K. B., & Thomsen, P. H. (2018). Rationale 
and design for cognitive behavioral therapy for anxiety disorders in children with autism spectrum disorder: a 
study protocol of a randomized controlled trial. Trials, 19(210). doi:10.1186/s13063-018-2591-x [doi] 
Kilburn, T. R., Sørensen, M. J., Thastum, M., Rapee, R. M., Rask, C. U., Arendt, K. B., & Thomsen, P. H. (2019). Group-
based Cognitive Behavioural Therapy for Anxiety Disorder in Children with Autism Spectrum Disorder: a 
feasibility study. Nordic Journal of Psychiatry, 73(4-5), 273-280. doi:10.1080/08039488.2019.1622153 
Kreslins, A., Robertson, A. E., & Melville, C. (2015). The effectiveness of psychosocial interventions for anxiety in 
children and adolescents with autism spectrum disorder: a systematic review and meta-analysis. Child and 
Adolescent Psychiatry and Mental Health, 9(22). doi:10.1186/s13034-015-0054-7 
Leyfer, O. T., Folstein, S. E., Bacalman, S., Davis, N. O., Dinh, E., Morgan, J., . . . Lainhart, J. E. (2006). Comorbid 
psychiatric disorders in children with autism: Interview development and rates of disorders. Journal of Autism 
and Developmental Disorders, 36(7), 849-861. doi:10.1007/s10803-006-0123-0 
Lyneham, H. J., Abbott, M. J., Wignall, A., & Rapee, R. M. (2003). The Cool Kids Child and Adolescent Anxiety Program 
Children's Workbook. Sydney, AU: Macquarie University. 
Lyneham, H. J., Chalfant, A., Kilburn, T. R., & Rapee, R. M. (2018 (in print)). The Cool Kids Anxiety Program: Autism 
Spectrum Disorder Adaptation. Children's Workbook (2nd ed.). Sydney, AU: Macquarie University. 
Lyneham, H. J., Sburlati, E. S., Abbott, M. J., Rapee, R. M., Hudson, J. L., Tolin, D. F., & Carlson, S. E. (2013). Psychometric 
properties of the Child Anxiety Life Interference Scale (CALIS). Journal of anxiety disorders, 27(7), 711-719. 
doi:10.1016/j.janxdis.2013.09.008 [doi] 
Parner, E. T., Schendel, D. E., & Thorsen, P. (2008). Autism Prevalence Trends Over Time in Denmark: Changes in 
Prevalence and Age at Diagnosis. Arch Pediatr Adolesc Med, 162(12), 1150–1156. Retrieved from 
doi:10.1001/archpedi.162.12.1150 
Perihan, C., Burke, M., Bowman-Perrott, L., Bicer, A., Gallup, J., Thompson, J., & Sallese, M. (2019). Effects of Cognitive 
Behavioral Therapy for Reducing Anxiety in Children with High Functioning ASD: A Systematic Review and 
Meta-Analysis. Journal of Autism and Developmental Disorders. doi:10.1007/s10803-019-03949-7 
Rapee, R. M. (2003). The influence of comorbidity on treatment outcome for children and adolescents with anxiety 
disorders. Behaviour research and therapy, 41(1), 105-112. doi:S0005796702000499 [pii] 
Rapee, R. M., Oar, E. L., Johnco, C. J., Forbes, M. K., Fardouly, J., Magson, N. R., & Richardson, C. E. (2019). Adolescent 
development and risk for the onset of social-emotional disorders: A review and conceptual model. Behaviour 
research and therapy, 123, 103501. doi:https://doi.org/10.1016/j.brat.2019.103501 
Reynolds, S., Wilson, C., Austin, J., & Hooper, L. (2012). Effects of psychotherapy for anxiety in children and adolescents: 
a meta-analytic review. Clinical Psychology Review, 32(4), 251-262.  
Schall, C., Wehman, P., & Carr, S. (2014). Transition from High School to Adulthood for Adolescents and Young Adults 
with Autism Spectrum Disorders. In F. Volkmar, B. Reichow, & J. McPartland (Eds.), Adolescents and Adults 
with Autism Spectrum Disorders. (pp. 41-60). New York, NY: Springer. 
Schniering, C. A., & Rapee, R. M. (2002). Development and validation of a measure of children’s automatic thoughts: the 
children’s automatic thoughts scale. Behaviour research and therapy, 40(9), 1091-1109.  
Scott, F. J., Baron-Cohen, S., Bolton, P., & Brayne, C. (2002). Brief report - Prevalence of autism spectrum conditions in 
children aged 5-11 years in Cambridgeshire, UK. Autism, 6(3), 231-237. doi:10.1177/1362361302006003002 
Silverman, W. K., & Albano, A. M. (1996). The Anxiety Disorders Interview Schedule for DSM-IV - Child and Parent 
versions. San Antonio, TX: Psychological Corporation. 
Silverman, W. K., Saavedra, L. M., & Pina, A. A. (2001). Test-retest reliability of anxiety symptoms and diagnoses with 
the Anxiety Disorders Interview Schedule for DSM-IV: child and parent versions. Journal of the American 
Academy of Child and Adolescent Psychiatry, 40(8), 937-944. doi:S0890-8567(09)60342-7 [pii] 
Simonoff, E., Pickles, A., Charman, T., Chandler, S., Loucas, T., & Baird, G. (2008). Psychiatric disorders in children with 
autism spectrum disorders: prevalence, comorbidity, and associated factors in a population-derived sample. 
Journal of the American Academy of Child and Adolescent Psychiatry, 47(8), 921-929. 
doi:10.1097/CHI.0b013e318179964f [doi] 
Spence, S. H. (1998). A measure of anxiety symptoms among children. Behaviour research and therapy, 36(5), 545-566. 
doi:S0005-7967(98)00034-5 [pii] 

77812_Protocol_210410_Version 5 
15 
 
StataCorp. (2019). Stata Statistical Software: Release 16. College Station, TX: StataCorp LLC.).  
Steinhausen, H. C., & Metzke, C. W. (2004). Differentiating the behavioural profile in autism and mental retardation and 
testing of a screener. European child & adolescent psychiatry, 13(4), 214-220.  
Storch, E. A., Arnold, E. B., & Lewin, A. B. (2013). The Effect of Cognitive-Behavioral Therapy Versus Treatment as Usual 
for Anxiety in Children With Autism Spectrum Disorders: A Randomized, Controlled Trial. J Am Acad Child 
Adolesc Psychiatry, 52(2), 132-142.  
Storch, E. A., Lewin, A. B., Collier, A. B., Arnod, E., De Nadai, A. S., Dane, B. F., . . . Murphy, T. K. (2015). A randomized 
controlled trial of cognitive-behavioral therapy versus treatment as usual for adolescents with autism 
spectrum disorders and comorbid anxiety. Depression and anxiety, 32(3), 174-181. doi:10.1002/da.22332 
pmid: 
Sukhodolsky, D. G., Bloch, M. H., Panza, K. E., & Reichow, B. (2013). Cognitive-Behavioral Therapy for Anxiety in Children 
With High-Functioning Autism: A meta-analysis. Pediatrics, 132(5), 1341-1350.  
Szatmari, P. (2003). The causes of autism spectrum disorders : Multiple factors have been identified, but a unifying 
cascade of events is still elusive. BMJ : British Medical Journal, 326(7382), 173-174. Retrieved from 
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1125046/ 
van Steensel, F. J., & Bogels, S. M. (2015). CBT for Anxiety Disorders in Children With and Without Autism Spectrum 
Disorders. Journal of consulting and clinical psychology, 83(3), 512-523. doi:doi: 10.1037/a0039108 
Volkmar, F. R., Reichow, B., & McPartland, J. C. (2014). Adolescents and Adults with Autism Spectrum Disorders. 
Switzerland: Springer. 
Wechsler, D. (2014). Wechsler intelligence scale for children - fifth edition. Bloomington, MN.: Pearson. 
WHO. (2010). International Statistical Classification of Diseases and Related Health Problems (10th Revision). (World 
Health Organization).  Retrieved from http://apps.who.int/classifications/icd10/browse/2010/en 
Wing, L., & Potter, D. (2002). The epidemiology of autistic spectrum disorders: is the prevalence rising? Mental 
retardation and developmental disabilities research reviews, 8(3), 151-161. doi:10.1002/mrdd.10029 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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16 
 
Figure 1. Flow diagram of participants through the study. The same diagram is relevant for the 3 
groups in Frederiksberg. 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
 
 
 
 
 
 
  
 
 
 
 
 
 
 
 
 
 
 
Individuals (age 13-17 yrs.) 
diagnosed with ASD experiencing 
sever anxiety symptoms in DK 
N≈1011 
Exclusion: (N≈5) 
- No confirmed ASD diagnosis 
- IQ < 70  
- Active psychosis 
- Untreated ADHD  
- Inability to speak Danish 
- Inability to attend group setting/   
sessions 
Interested in participating 
N≈23 
Anxiety diagnosed (on-line) with 
ADIS/CP + questionnaires 
N≈18 
Participating in Cool Teens ASD 
treatment program 
N=15 
Post assessment 
3½ month booster 
Exclusion: (N≈3) 
- Not fulfilling an anxiety 
diagnosis on ADIS C/P 
 
Treatment  
13 wks. for each group 
Enrolment 
FU 3 months 
Follow-up assessment  
Post approx. 1 
wk. after 
treatment