The Momentum Program: Online Cognitive Behavioural Therapy (CBT) for Adolescent Anxiety and Depression Comorbidity

INTERVENTION: The design involves a two‐arm parallel‐group RCT where adolescents aged 13‐17 years with comorbid anxiety and depression will be randomly assigned to either the online comorbid (COM) program condition targeting comorbid anxiety and depression, or the online primary diagnosis (PRI) program condition targeting the primary presenting problem (anxiety or depression). Both arms (i.e. Intervention Arm 1 and Intervention Arm 2) will receive an online intervention program. The online programs will be accessed via the Momentum platform (https://momentumhub.org.au). The online interventions on the Momentum platform are self‐directed and there is no contact with a therapist or a psychologist. The intervention program will be either 7 (PRI programs) or 10 (COM programs) sessions. The sessions will become available weekly. Each session does not have to be completed in one go, but each session will need to be completed before the participants move on to the next one. The users will receive automated reminders related to session availability. On the home page, the users will be able to monitor how far they are in their assigned program. The Momentum program sessions have been co‐designed with young people to ensure they are engaging and interactive. Sessions include the use of images, interactive elements, pop‐up messages, and quizzes that provide immediate feedback. Each session comprises approximately 30 slides and takes an estimated 45 minutes to complete. Number of sessions will change depending on the intervention arms. Homework assignments can be completed online or can be printed out. Each session follows a similar format: (1) Feelings check‐in (where the young person completes brief anxiety and depression questionnaires); (2) A review of homework from the previ CONDITION: Anxiety;Depression; ; Anxiety ; Depression Mental Health ‐ Anxiety Mental Health ‐ Depression PRIMARY OUTCOME: Youth anxiety symptoms; ; Anxiety symptoms will be assessed with the Spence Children’s Anxiety Scale (SCAS; Spence, 1998).[Pre‐intervention; Post‐completion of program (primary endpoint); 6‐month post‐baseline follow up; 12‐month post‐baseline follow up] Youth depressive symptoms; ; Depressive symptoms will be assessed with the Centre for Epidemiological Studies Depression Scale for adolescents (CES‐D; Radloff, 1991). [Pre‐intervention ; Post‐completion of program (primary endpoint); 6‐month post‐baseline follow up; 12‐month post‐baseline follow up; ] SECONDARY OUTCOME: Quality of life ; ; Quality of life will be assessed with the Child Health Utility 9 Inde X(CHU9D; Ratcliffe et al., 2012).[Pre‐intervention ; Post‐completion of program ; 6‐month post‐baseline follow up ; 12‐month post‐baseline follow up] Treatment satisfaction and acceptability ; ; Treatment satisfaction and acceptability will be assessed at post‐intervention with a 6‐item questionnaire adapted from March et al. (2009), in which young people are asked to rate their program satisfaction on a 5‐point scale. [Post‐completion of program] INCLUSION CRITERIA: Following registration and the initial assessment process that is part of the open access Momentum Platform, adolescents aged 13‐17 years who are found to demonstrate comorbid anxiety and depression symptoms will be invited to participate in the study. Participants must be willing to participate in either of the two conditions (COM or PRI).