Development, Feasibility and Acceptability of an iCBT Intervention for Adolescents With Anxiety

An online diagnostic assessment tool that assesses DSM-5 anxiety disorders and specific phobias. Each present diagnosis is assigned a clinician-rated severity score ranging from 0 (minimal/absent) to 4 (pervasive). Typically subclinical disorders would receive a rating of 0 or 1, and clinical disorders a rating of 1 to 4.

A 44-item self-report questionnaire assessing anxiety symptoms of six different anxiety disorders in DSM-IV: generalized anxiety, panic/agoraphobia, social phobia, separation anxiety, obsessive compulsive disorder and physical injury fears. Symptoms are rated on a 4-point frequency scale ranging from 0 (never) to 3 (always) (min. = 0; max. = 114). A higher score indicates increased symptom severity. The Danish version has demonstrated good psychometric properties

CALIS measures the impact of youth anxiety on various areas of life functioning such as school, extracurricular activities, family life and friendships. Impact is reported on a 5-point severity scale ranging from 0 (not at all) to 4 (a lot) (min. = 0; max = 56). A summed score of all items is used to indicate level of impact, where a higher score indicates greater impairment. CALIS has shown satisfactory internal consistency and moderate test-retest reliability.

A 9-item questionnaire used to measure youth depressive symptoms and suicidal ideation within the past 2 weeks. Symptoms are rated on a frequency scale ranging from 0 (not at all) to 3 (nearly everyday). The symptoms are evaluated independently by adolescents. A summed score of all 9 items is used to indicate symptom severity (min. = 0; max. = 27), where a higher score indicates greater severity and possible presence of a depressive disorder.

An 8-item questionnaire used to measure general satisfaction with a received treatment. Satisfaction is reported using a 4-point scale ranging from 1 (lowest degree of satisfaction) to 4 (highest degree of satisfaction). A summed score of all items is used to indicate level of satisfaction (min = 8; max. = 32). The scale has shown high internal consistency and concurrent validity.

A 5-item self-report questionnaire assessing quality of life and self-rated health. The items cover five domains: mobility, selfcare, usual activities, pain/discomfort, and anxiety and depression. Each domain is assigned a score from 1 (no health problems) to 3 (a lot of health problems) and based on these scores, a unique health state can be identified for each participant.

A 20-item questionnaire used to monitor the occurrence of negative effects in psychological treatments. Participants are asked to report whether specific things have occurred or not during treatment, how negatively it affected them, and whether the negative affect is attributed to the received treatment or other circumstances. The items can be summed together in order to get a frequency measure of the number of negative effects the respondents have experienced, divided by treatment or other circumstances. NEQ shows acceptable psychometric properties.

A 10-item questionnaire used to assess the subjective experience of usability of a computer system. Participants are asked to score 10 different statements about the computer system on a 5-point scale from 0 (strongly disagree) to 4 (strongly agree). A higher summed score indicates greater comfortability with the computer system. A Danish version of the SUS has been validated in a mental health care setting.

Number of words in the in-program text modules and number of words in messages sent by both participant and therapist.

Number of logins in the digital platform.

Therapist time spent giving feedback reported in minutes.

Sociodemographic measures include participants' age and gender, and parents' level of education, and primary caregiver in case of single parents.