This study implements a parent-led, flexible, individually-tailored cognitive-behavioral intervention for children with ASD and anxiety.

Autism spectrum disorder (ASD) affects as many as 1 out of 59 individuals, with many higher-functioning youth not diagnosed until school-age or later. This equates to ~102,000 children under the age of 14 years in the state of Texas alone. Significant impairment in social and adaptive functioning are common, as are comorbid behavioral health disorders, with anxiety disorders affecting between 50-80% of youth with ASD. Given the relative frequency of anxiety disorders among children with ASD, the associated impairment, and worsening trajectory over time without intervention, there is a great need for treatment that specifically addresses anxiety-related symptoms in ASD. Cognitive-behavioral therapy (CBT) has been established as a first-line treatment for anxiety disorders among youth with and without ASD. A particular form of CBT, Behavioral Intervention for Anxiety in Children with ASD (BIACA), has demonstrated efficacy in a number of studies. However, treatment is delivered by therapists as "full-packages" (i.e., 12-16 clinic sessions), which can be therapist-intensive, costly, impractical for families, and not responsive to parental preferences. Alternatives approaches, such as parent-led, stepped-care models that improve accessibility, are efficient, provide personalized care, and lower mental health treatment cost, are greatly needed. Stepped-care models provide a lower-intensity first step (e.g., parent-led, less costly, and more convenient for parents) as the initial treatment with the assumption that a proportion of individuals will respond to the first step and others will need to step up to more intensive treatment. Matching treatment to families' needs and tailoring subsequent treatment may be an efficient and effective approach, as well as consistent with parents' desire to help their child. Given this, together with the substantial impairment associated with clinical anxiety in individuals with ASD across the age span, this study implements a parent-led, flexible, individually-tailored cognitive-behavioral intervention for children with ASD and anxiety.

Inclusion Criteria:

• Child is between the ages 4-14 years at consent/assent.
• The child meets criteria for ASD.
• The child meets criteria for clinically significant anxiety and/or OCD symptoms.
• Anxiety and/or OCD is the primary presenting problem.
• One parent/guardian is able and willing to attend.
• The child has a Full Scale and Verbal Comprehension Intelligence Quotient >70.

Exclusion Criteria:

• The child has a diagnosis of lifetime DSM-5 bipolar disorder, psychotic disorder, and/or intellectual disability.
• The child has severe current suicidal/homicidal ideation and/or self-injury requiring medical intervention.
• The child is receiving concurrent psychotherapy for anxiety.
• Initiation of a psychotropic medication less than 4 weeks prior to study enrollment or a stimulant/psychoactive medication less than 2 weeks prior to study enrollment.

The rater is unaware of treatment status, that is if the child continues to receive treatment after Step 1 (versus being in maintenance).