ICBT for OCD in Children With Autism

The purpose of this trial is to evaluate the clinical efficacy, the cost-effectiveness and the effect durability of a therapist-guided, internet-delivered cognitive-behavior therapy intervention for obsessive-compulsive disorder (OCD) in children and adolescents with autism. A process evaluation of the treatment will also be conducted.

Primary objective: To determine the clinical efficacy of autism-adapted internet-delivered exposure with response prevention (I-ERP) in reducing OCD symptom severity (as measured by the Children's Yale Brown-Obsessive Compulsive Scale; CY-BOCS) in children and adolescents with OCD and autism spectrum disorder (ASD), compared with an active control intervention of high ecological validity (internet-delivered stress management; I-SM).

Secondary objectives:

1. To establish the 6-month durability of the treatment effects in a naturalistic follow-up.
2. To conduct a health economic evaluation of I-ERP, compared with I-SM, at the primary endpoint (3-month follow-up) from the health organisation payer, health care sector, and societal perspectives.
3. To conduct a process evaluation with a subset of participants allocated to the I-ERP arm, focusing on implementation, mechanisms of impact, and context.

Type of trial: A multisite parallel-group randomised controlled superiority trial, with embedded health economic and process evaluation.

Rationale: OCD and ASD are two frequently co-occuring disorders, associated with significant impairments in daily life. Cognitive-behavioural therapy (CBT) specifically adapted to ASD is a promising treatment for this patient group, but further research is needed to fully establish its efficacy. Furthermore, ASD-adapted CBT for OCD is a highly specialised treatment, not accessible for most patients. Offering treatment in a digital format could dramatically increase treatment availability for these children.

Planned trial sites: The study will be coordinated from the Department of Clinical Neuroscience at Karolinska Institutet (the Sponsor). There will be three collaborating study sites: BUP OCD och relaterade tillstånd (Region Stockholm), BUP Specialmottagning (Västra Götalandsregionen), and BUP Skåne (Region Skåne). Each of the three sites will assess and treat participants from their own region, and occasionally from adjacent regions.

Trial design and methods: All potential participants are initially screened via the telephone or at one of the three participating centres. If screening is positive, an inclusion assessment will follow. Individuals who are eligible and have consented to participate in the trial will be randomised to one of two trial arms. In one arm, participants will receive 12 modules of therapist- and parent-guided I-ERP for OCD adapted for autism. In the active comparator arm, participants will receive 12 modules of therapist- and parent-guided I-SM. Participants in the comparator group will be offered to cross-over to the I-ERP intervention after the primary endpoint.

Participants will complete outcome measures at baseline (week 0), post-treatment (week 12), and 3- and 6-months post-treatment. The primary outcome variable is the clinician-reported Children's Yale Brown-Obsessive Compulsive Scale (CY-BOCS), and the primary endpoint is the 3-month follow-up after treatment.

Secondary outcomes include measures of self-reported OCD symptoms, family accommodation, functional impairment, and depressive symptoms. Health-related quality of life and resource use will be collected for the health economic evaluation. Follow-up assessments will be conducted at the clinic or via videoconferencing, in both cases complemented with online questionnaires.

A subset of participants will participate in a process evaluation of the I-ERP intervention.

Sample: A total of 220 autistic children and adolescents diagnosed with OCD and their primary caregivers.

Statistical methodology and analysis: Data will be analysed using a pre-specified intention-to-treat statistical analysis plan. The primary outcome will be analysed using a linear mixed effects model. Secondary outcomes will be analysed using analogous methods. A health economic evaluation of the intervention from the health organisation payer, health care sector, and societal perspectives will also be conducted, as well as a process evaluation including both quantitative and qualitative measures.

Eligibility Criteria:
Inclusion Criteria:

1. A diagnosis of autism, based on the diagnostic criteria of the 4th or 5th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM) or the 10th edition of the International Classification of Diseases (ICD-10). Informed by the parent/caregiver and subsequently confirmed by review of the medical record or the neurodevelopmental assessment report. A diagnosis of autism will be considered present if it was established with validated instruments, such as the Autism Diagnostic Interview-Revised (ADI-R), the Autism Diagnostic Observation Schedule (ADOS) edition 1 or 2 or the Diagnostic Interview for Social and Communication Disorders (DISCO; autism or ASD cut-offs).
2. A DSM-5 or ICD-10 diagnosis of OCD. Confirmed by the assessor at the inclusion assessment, based on a structured diagnostic interview.
3. A total score of ≥16 on the CY-BOCS. Confirmed by the assessor at the inclusion assessment.
4. Age between 7 and 17 years. Confirmed by the caregiver and subsequently by the medical record system.
5. Ability to read and write Swedish. Confirmed by the caregiver at the telephone screening or/and the inclusion assessment.
6. Regular access to a computer or a smartphone/tablet connected to the internet, and a mobile phone to receive text messages. Confirmed by the caregiver at the telephone screening or/and inclusion assessment.
7. A parent/caregiver able to participate in the treatment alongside their child. Confirmed by the caregiver at the telephone screening or/and the inclusion assessment.

Exclusion Criteria:

1. Global intellectual disability. Informed by the parent/caregiver and subsequently confirmed by review of the medical record or the neurodevelopmental assessment report, and additionally estimated with the two subtests matrix reasoning and similarities from the Wechsler Intelligence Scale for Children - fifth edition (WISC-V) or Wechsler Adult Intelligence Scale - fourth edition (WAIS-IV).
2. Comorbid psychotic disorder, bipolar disorder, severe eating disorder, severe depression, alcohol/substance dependence or hoarding disorder. Confirmed by the caregiver at the telephone screening and subsequently by the assessor at the inclusion assessment based on the structured diagnostic interview and, if required, the medical record.
3. Current suicidal intent or a previous suicide attempt within the last 12 months. Confirmed by the assessor at the inclusion assessment and, if required, the medical record.
4. Main symptom presentation consists of hoarding symptoms. Confirmed by the assessor at the inclusion assessment.
5. Completed CBT for OCD within the last 12 months prior to the inclusion assessment (defined as at least 5 sessions of CBT including ERP). Confirmed by the caregiver at the telephone screening or/and inclusion assessment and, if required, the medical record.
6. Simultaneous psychological treatment for OCD or anxiety. Confirmed by the caregiver at the telephone screening and/or inclusion assessment.
7. Initiation, dosage change or cessation of medication for OCD (primarily selective serotonin reuptake inhibitors, SSRIs) or behavioural symptoms of ASD (atypical antipsychotics) within the 6 weeks prior to the baseline assessment. Confirmed by the caregiver at the telephone screening and the inclusion assessment and, if required, the medical record.
8. Having a close relationship to an already included participant (e.g., sibling, cousin), to avoid being randomised into two different arms, with the risk of information "leaking" between the groups. Confirmed by the caregiver or assessor at the telephone screening and/or at the inclusion assessment.