Internet-Delivered Cognitive Behavioral Intervention for Youths With Anxiety Disorders

Diagnostic Interview for Anxiety, Mood, and OCD and Related Neuropsychiatric Disorders - Child and Adolescent Version (DIAMOND-KID)

Used to assess anxiety disorders and psychiatric comorbidity at baseline and anxiety disorders and major depression at follow-ups. Clinician-rated.

Time frame: Baseline; post-treatment (window of 12 to 18 weeks post-enrollment); 3-months post-treatment (window of 23 to 31 weeks post-enrollment).

Clinical Global Impression Scale - Severity (CGI-S)

Used to assess overall anxiety severity. Clinician-rated. Ratings are reported on a seven-graded scale from 1 ("Normal, not at all ill") to 7 ("Among the most extremely ill patients").

Time frame: Baseline; post-treatment (window of 12 to 18 weeks post-enrollment); 3-months post-treatment (window of 23 to 31 weeks post-enrollment).

Clinical Global Impression Scale - Improvement (CGI-I)

Used to assess level of improvement compared to admission. Clinician-rated. This single item scale ranges from 1 ("Very much improved") to 7 ("Very much worse").

Time frame: Baseline; post-treatment (window of 12 to 18 weeks post-enrollment); 3-months post-treatment (window of 23 to 31 weeks post-enrollment).

Children's Global Assessment Scale (CGAS)

Used to assess global impairment. Clinician-rated. The CGAS is a single item scale that ranges from 1 to 100, with a higher value indicating better functioning.

Time frame: Baseline; post-treatment (window of 12 to 18 weeks post-enrollment); 3-months post-treatment (window of 23 to 31 weeks post-enrollment).

Therapist time

Therapist time: preparation time, support time in platform, support time via telephone, support time via videoconference, and documentation time. Reported in minutes per participant per week for each variable as well as combined.

Time frame: Consecutively throughout the 12 week treatment period.

Module completion

Completion of modules in the internet platform for each child/adolescent and each caregiver. Ranges from 0 to 12 modules. Reported separately for children, adolescents, caregivers of children, and caregivers of adolescents.

Time frame: Consecutively throughout the 12 week treatment period.

Number of participants with concomitant interventions

Used to assess potential other treatments during the study period. Clinician-rated.

Time frame: Post-treatment (window of 12 to 18 weeks post-enrollment); 3-months post-treatment (window of 23 to 31 weeks post-enrollment).

Revised Child Anxiety and Depression Scale - Child version (RCADS-C)

Used to assess anxiety symptoms. Child/adolescent-reported. The RCADS version used in the present study is the 47-item version which ranges from 0 to 141 points, with higher scores indicating more severe internalizing symptoms.

Time frame: Baseline; post-treatment (window of 12 to 18 weeks post-enrollment); 3-months post-treatment (window of 23 to 31 weeks post-enrollment).

Child Anxiety Life Interference Scale - Revised - Child version (CALIS-R-C)

Used to assess life interference and impairment associated with childhood anxiety. The scale ranges from 0 to 36 points, with higher scores indicating higher interference and impairment. Child/adolescent-reported.

Time frame: Baseline; post-treatment (window of 12 to 18 weeks post-enrollment); 3-months post-treatment (window of 23 to 31 weeks post-enrollment).

Patient Health Questionnaire-2 (PHQ-2)

Used to assess mood and anhedonia symptoms. Child/adolescent-reported. Scores range from 0 to 6 points, with higher scores indicating more severe internalizing symptoms.

Time frame: Baseline; 3, 6, and 9 weeks into treatment; post-treatment (window of 12 to 18 weeks post-enrollment); 3-months post-treatment (window of 23 to 31 weeks post-enrollment).

Generalized Anxiety Disorder-2 (GAD-2)

Used to assess anxiety symptoms. Child/adolescent-reported. Scores range from 0 to 6 points, with higher scores indicating more severe anxiety.

Time frame: Baseline; 3, 6, and 9 weeks into treatment; post-treatment (window of 12 to 18 weeks post-enrollment); 3-months post-treatment (window of 23 to 31 weeks post-enrollment).

Well-being

Used to assess well-being, operationalized as satisfaction with life, overall happiness, and how much the person would change about their life if they could. Child/adolescent-reported. Scores range from 3 to 33 points, with higher scores indicating higher well-being.

Time frame: Baseline; 3, 6, and 9 weeks into treatment; post-treatment (window of 12 to 18 weeks post-enrollment); 3-months post-treatment (window of 23 to 31 weeks post-enrollment).

Mood and Feelings Questionnaire (MFQ) - Suicidality item

Single item taken from the Mood and Feelings Questionnaire (MFQ) used to assess suicidal ideation. Child/adolescent-reported. Scores range from 0 to 3 points, with higher scores indicating higher suicidal ideation.

Time frame: Baseline; 3, 6, and 9 weeks into treatment; post-treatment (window of 12 to 18 weeks post-enrollment); 3-months post-treatment (window of 23 to 31 weeks post-enrollment).

Experiences of CBT - Child version

Used to assess experiences of receiving CBT. Child/adolescent-reported. The scale consists of 7 items (baseline), 12 items (3, 6, and 9 weeks into treatment; post-treatment). The baseline version consists of two separate scores ranging from 5 to 50 points (higher scores indicate a better treatment experience) and from 2 to 20 points (higher scores indicate a higher level of distress and interference). The mid- and post-treatment versions consist of three separate scores ranging from 9 to 90 points (higher scores indicate a better treatment experience), from 2 to 20 points (higher scores indicate a higher level of distress and interference), and from 1 to 6 points (higher scores indicate more time spent on treatment).

Time frame: Baseline; 3, 6, and 9 weeks into treatment; post-treatment (window of 12 to 18 weeks post-enrollment).

Working alliance - Child version

Used to assess the participant's perceived working alliance with their therapist. Child/adolescent-reported. The scale ranges from 0 to 36 points, with higher scores indicating better working alliance.

Time frame: 3, 6, and 9 weeks into treatment.

Adverse events questionnaire - Child version (AEQ-C)

Used to assess adverse events/effects. Child/adolescent-reported. The scale consists of 22 yes/no items (score range 0-22 points) with higher scores indicating more present adverse events. For each adverse event that is present, there is also a rating of whether the adverse event is thought to be related to the provided treatment (yes or no).

Time frame: 3, 6, and 9 weeks into treatment; post-treatment (window of 12 to 18 weeks post-enrollment).

Client Satisfaction Questionnaire - Child version (CSQ-8-C)

Used to assess treatment satisfaction. Child/adolescent-reported. The scale ranges from 9 to 36 points, with higher scores indicating greater satisfaction.

Time frame: Post-treatment (window of 12 to 18 weeks post-enrollment).

Need for treatment - Child version

Used to assess the need of treatment for anxiety symptoms. Child/adolescent-reported. This single item scale ranges from 0 to 5 points, with higher scores indicating a higher need for treatment.

Time frame: Baseline; post-treatment (window of 12 to 18 weeks post-enrollment); 3-months post-treatment (window of 23 to 31 weeks post-enrollment).

Revised Child Anxiety and Depression Scale - Parent version (RCADS-P)

Used to assess anxiety symptoms. Caregiver-reported. The RCADS version used in the present study is the 47-item version which ranges from 0 to 141 points, with higher scores indicating more severe internalizing symptoms.

Time frame: Baseline; post-treatment (window of 12 to 18 weeks post-enrollment); 3-months post-treatment (window of 23 to 31 weeks post-enrollment).

Child Anxiety Life Interference Scale - Revised - Parent version (CALIS-R-P)

Used to assess life interference and impairment associated with childhood anxiety. Caregiver-reported. The scale ranges from 0 to 36 points, with higher scores indicating higher interference and impairment.

Time frame: Baseline; post-treatment (window of 12 to 18 weeks post-enrollment); 3-months post-treatment (window of 23 to 31 weeks post-enrollment).

Experiences of CBT - Parent version

Used to assess experiences of receiving CBT. Child/adolescent-reported. The scale consists of 7 items (baseline), 12 items (3, 6, and 9 weeks into treatment; post-treatment). The baseline version consists of two separate scores ranging from 5 to 50 points (higher scores indicate a better treatment experience) and from 2 to 20 points (higher scores indicate a higher level of distress and interference). The mid- and post-treatment versions consist of three separate scores ranging from 9 to 90 points (higher scores indicate a better treatment experience), from 2 to 20 points (higher scores indicate a higher level of distress and interference), and from 1 to 6 points (higher scores indicate more time spent on treatment).

Time frame: Baseline; 3, 6, and 9 weeks into treatment; post-treatment (window of 12 to 18 weeks post-enrollment).

Working alliance - Parent version

Used to assess the caregiver's perceived working alliance with their therapist. Caregiver-reported. The scale ranges from 0 to 36 points, with higher scores indicating better working alliance.

Time frame: 3, 6, and 9 weeks into treatment.

Adverse events questionnaire - Parent version (AEQ-P)

Used to assess adverse events/effects. Parent-reported. The scale consists of 22 yes/no items (score range 0-22 points) with higher scores indicating more present adverse events. For each adverse event that is present, there is also a rating of whether the adverse event is thought to be related to the provided treatment (yes or no).

Time frame: 3, 6, and 9 weeks into treatment; post-treatment (window of 12 to 18 weeks post-enrollment).

Client Satisfaction Questionnaire - Parent version (CSQ-8-P)

Used to assess treatment satisfaction. Caregiver-reported. The scale ranges from 9 to 36 points, with higher scores indicating greater satisfaction.

Time frame: Post-treatment (window of 12 to 18 weeks post-enrollment).

Need for treatment - Parent version

Used to assess the need of treatment for anxiety symptoms. Caregiver-reported. This single item scale ranges from 0 to 5 points, with higher scores indicating a higher need for treatment.

Time frame: Baseline; post-treatment (window of 12 to 18 weeks post-enrollment); 3-months post-treatment (window of 23 to 31 weeks post-enrollment).

Avoidance and Fusion Questionnaire for Youth (AFQ-Y8)

Used to assess psychological inflexibility. Child/adolescent-reported. The scale ranges from 0 to 32 points, with higher scores indicating greater psychological inflexibility.

Time frame: Baseline.

The Cognitive-attentional Syndrome Questionnaire (CAS-1)

Used to assess dysfunctional metacognitive beliefs. Child/adolescent-reported. The questionnaire consists of four domains. Each item of the three first domains is scored on a 0-8 point scale. Each item of the fourth domain is score on 0-100 scale. Higher scores indicates more dysfunctional metacognitive beliefs.

Time frame: Baseline.

Swanson, Nolan, and Pelham Rating Scale (SNAP-IV)

Used to assess attention difficulties, hyperactivity, impulsivity, and oppositional symptoms. Caregiver-reported. Each item is scored from 0 to 3 points. The item scores are then summarized in domains: inattention (items 1-9), hyperactivity-impulsivity (items 11-19) and oppositional (items 21-28). Items 10, 20 and 29 are not included in any of the domains. Higher scores indicate greater attention difficulties, hyperactivity, impulsivity, and oppositional symptoms.

Time frame: Baseline.

Core autism traits - Child version

Used to assess core autism traits. Child/adolescent-reported. The scale ranges from 0 to 36 points, with higher scores indicating greater autism traits.

Time frame: Baseline.

Core autism traits - Parent version

Used to assess core autism traits. Caregiver-reported. The scale ranges from 0 to 36 points, with higher scores indicating greater autism traits.

Time frame: Baseline.

Focus groups

Qualitative data will be gathered through focus group interviews with the aim of generating novel ideas on how to enhance the ICBT intervention to better suit its target group. Four different types of focus groups will be compiled from the open clinical trial participants: children aged 8-12 years, b) caregivers of these children; c) adolescents aged 13-17 years; and d) caregivers of these adolescents.

Time frame: From week 12 and onwards (no specified end date in the study protocol).