Internet-Based Cognitive Behavioural Therapy (iCBT) for Anxiety and Depression in Singapore

This multi-agency collaboration study involves partners from MOH Office for Healthcare Transformation (MOHT), Agency of Integrated Care (AIC), and selected Community Intervention Team (COMIT) providers. Participants will be recruited from COMIT providers, which may include patients referred from the primary healthcare sector. Study visits (e.g. iCBT programme, questionnaires, counsellor check-ins) will be conducted online and/or at COMIT sites, where COMIT are the service providers with AIC.

Research procedures were developed with the MOHT co-investigators to design the study protocol, recruitment and operational workflows, and risk management protocols. MOHT leads the development of the iCBT programme, including but not limited to the mobile application interface, intervention materials, interactive exercises, and homework assignments, which would be tested before rolling out to the research participants. Study evaluations (e.g. data analysis, literature reviews, drafting of manuscripts) will be conducted at NUS.

The study comprises of two components: (1) quantitative and (2) qualitative research.

• Quantitative Study Design: Clinical-Effectiveness The proposed study design will be a two-arm (intervention-control), single-blind (evaluator-blind) randomised controlled trial to evaluate the clinical effectiveness of iCBT for anxiety and depression in Singapore's primary care and community setting. 390 participants will be recruited and randomised 1:1 to intervention (N = 195) or control (N = 195) groups using stratified block randomisation.

Participants in the intervention group will be required to download the iCBT mobile application on their mobile devices. The guided iCBT intervention will consist of 8 weeks of 8 online modules (1 module per week) covering core CBT techniques, including interactive exercises and homework assignments delivered via the iCBT programme on a mobile application. There is no prescribed duration for each module, participants may complete the weekly exercises at their own pace within the eight-week period. COMIT counsellors will schedule regular check-ins with the participants at Week 3, 5, and end of Week 8 via face-to-face or video sessions to introduce the treatment rationale, practise skills, and assess the participants' progress. The control group will continue usual care, including but not limited to care from GP consultations, standard face-to-face CBT, and/or referral to other mental health services.

All participants - both intervention and control groups - are required to complete up to 6 study visits over the course of 8 to 10 months, with each study visit taking approximately 1 to 2 hours for completion of questionnaires pertaining to primary and secondary outcome measures and/or counsellor check-ins, where applicable. The primary outcome measures include PHQ-9 and GAD-7 while secondary outcome measures include WHO Disability Assessment Schedule (WHODAS), patient satisfaction, healthcare utilisation, and cost-effectiveness. Please refer to the visit schedule below:

• Pre-treatment/Baseline - Week 1
• Mid-treatment - Week 5
• Post-treatment - Week 8
• 3 months from baseline
• 6 months from baseline

2a) Qualitative Study Design: Patients Qualitative components will also be incorporated into the project to explore patients' experiences, perceptions, and preferences regarding iCBT for depression and anxiety disorders. The qualitative study will provide deeper insights into the factors that influence treatment engagement, adherence, and satisfaction, which are not fully captured by quantitative measures alone.

Selected participants in the intervention group will be invited for a 1-hour semi-structured interview. Participants will be recruited using purposive sampling to ensure representation of key groups relevant to the implementation of iCBT. Specifically, patients will be selected from among those who have completed the iCBT programme, with a diverse subset based on age, gender, diagnosis (depression or anxiety), symptom severity, and completion status (completers and non-completers). This approach ensures variation in experiences and perspectives.

An interview guide will be developed to explore participants' experiences with iCBT and will include open-ended questions to allow participants to share their perspectives in their own words. This semi-structured interview will be conducted by qualified personnel assigned by the study team. This is planned as a 1-1 Interview. The interview will be conducted via video-conferencing, and the session will be audio-recorded and transcribed. During the semi-structured interview for the qualitative survey, participant quotes may be included in research publications or presentations, provided consent is obtained. All quotes will be anonymised.

Key topics to be covered in the interviews include:

• Treatment Experience: Participants' overall experience with iCBT.

• Support from Therapists: The value of guidance from therapists (if applicable) in their treatment journey, including the quality and frequency of support received.

• Adherence and Engagement: Factors that influenced their adherence to the programme, including motivation, barriers, and facilitators.

• Suggestions for Improvement: Recommendations for improving the iCBT programme based on their experience.

2b) Qualitative Study Design: Service Providers A parallel qualitative study involving service providers is required to contextualise trial findings, identify implementation barriers and enablers and inform national scale-up and policy decisions. It aims to explore service providers' experiences, perceptions and contextual factors influencing the implementation of iCBT within routine primary-care and community mental-health services participating in this trial.

This qualitative descriptive study comprises of semi-structured in-depth interviews that adopt an implementation science lens, drawing on constructs from:

• RE-AIM (Reach, Effectiveness, Adoption, Implementation, Maintenance), and
• Consolidated Framework for Implementation Research (CFIR) domains (intervention characteristics, inner setting, outer setting, individual characteristics, and implementation process).

A purposive sampling approach will be used to ensure diversity across professional roles, practice settings and levels of experience with digital mental health interventions. Sampling will continue until thematic saturation is reached (anticipated n = 10-20 participants), consistent with prior qualitative iCBT implementation studies in healthcare services. Service providers will be recruited directly by the research team or through an email blast to ensure participation is entirely voluntary. Each interview will last approximately 45-60 minutes via secure videoconferencing or in person at AIC office, MOHT office or the COMIT site where the service provider is based at, and the session will be audio-recorded and transcribed. Participant quotes may be included in research publications or presentations, where all quotes will be anonymised.

Key topics to be covered in the interviews include:

• Initial perceptions and expectations of iCBT
• Experiences integrating iCBT into routine workflows
• Perceived clinical value and patient suitability
• Digital usability and training adequacy
• Impact on workload, time, and role boundaries
• Organisational and system-level enablers or constraints
• Reflections on sustainability and future improvements

• Quantitative Study - Patients

Inclusion criteria

• Age ≥21 years
• Tier 2 - 3 depression and/or anxiety based on PHQ-9 and GAD-7 scores

• PHQ-9 score of 5 to 19
• GAD-7 score of 5 to 14
• Able to provide informed consent

Exclusion criteria

• Unable to read or understand English (Primary 6 level)
• Unable to use the internet (e.g. due to lack of internet access or insufficient digital literacy)
• Does not possess a mobile device or is not able to access the iCBT application
• Actively experiencing psychosis
• Suspected with personality disorder
• Primary concern is obsessive compulsive disorder (OCD)
• Tier 4 patients with severe depression or anxiety

• PHQ-9 score of 20 and above
• GAD-7 score of 15 and above
• Any suicidal risk or ideation

• PHQ-9 Question 9 score of more than 2
• Qualitative Study - Service Providers

Inclusion criteria

• Are currently or previously have been involved in the delivery, supervision, or implementation of the iCBT programme
• Have had direct experience supporting patients enrolled in the study
• Able to provide informed consent

Exclusion criteria

• Have no direct involvement in the iCBT programme; or
• Have had insufficient exposure to the programme, defined as managing fewer than one referred case or less than one month of involvement at the time of recruitment.
• Conflict of interest or Supervisory Hierarchy Concerns - Individuals whose participation may create perceived coercion or introduce bias
• Inability to provide informed consent