Protocol for a randomised controlled trial investigating self-help email messages for sub-threshold depression: the...

Area of Science:

• Mental Health Promotion
• Digital Health Interventions
• Preventive Psychiatry

Background:

• Sub-threshold depression is prevalent, impairs functioning, and elevates the risk of major depression.
• Existing psychological treatments are effective but costly.
• A cost-effective alternative involves health promotion campaigns focused on self-help strategies for depression.

Purpose of the Study:

• To evaluate the efficacy of a low-cost, email-based mental health promotion campaign.
• To assess the campaign's impact on self-help behavior and prevention of more severe depression.
• To determine if an automated preventive email intervention can improve coping strategies and reduce depressive symptoms.

Main Methods:

• A randomized controlled trial involving adults (18+) with sub-threshold depression (Patient Health Questionnaire-9).
• Participants were recruited via the study website (moodmemos.com) and randomized.
• Intervention group received twice-weekly emails with self-help advice; control group received general depression information for six weeks.

Main Results:

• Outcomes measured at baseline, midpoint, end of intervention, and six-month follow-up.
• Assessed variables included depression symptoms, major depression incidence, distress, functioning, coping strategies, and self-efficacy.
• Primary hypothesis: Mood Memo emails with coping strategies reduce symptoms and prevent major depression compared to controls.

Conclusions:

• Public health promotion strategies can be adapted for mental health prevention.
• This study investigates the potential of a low-cost, scalable email campaign.
• The research explores the campaign's ability to enhance self-help coping and prevent depression in adults experiencing sub-threshold symptoms.