Systematic Review Protocol: The Effects of Theory-Based Interventions for Self-Help Practices in the Management of Mild to Moderate Depression

BackgroundDepression is a leading global cause of disability, significantly affecting individuals quality of life and contributing to a substantial worldwide health burden. Self-help practices have emerged as cost-effective and scalable strategies for managing mild to moderate depression, empowering individuals to take an active role in their mental health care. Theory-based interventions, which are grounded in established psychological frameworks, provide a systematic approach to designing, implementing and evaluating these self-help practices. However, despite the growing availability of self-help interventions, their effectiveness varies, and many lack a solid theoretical foundation. Summarized evidence of the effects of theory-based interventions remains limited. ObjectivesThis systematic review aims to evaluate the effects of theory-based interventions incorporating self-help practices in reducing depressive symptoms severity among adults with mild to moderate depression. MethodsThe review will follow PRISMA guidelines and has been registered with the International Prospective Register of Systematic Reviews (PROSPERO). Randomised trials evaluating theory-based interventions, such as Cognitive Behavioral Therapy (CBT), Acceptance and Commitment Therapy (ACT), and Mindfulness-Based Interventions (MBIs), delivered via digital platforms will be included. Studies will be identified through searches of PubMed, Scopus, Web of Science, Science Direct and Cochrane bibliographic databases. Data extraction and risk of bias assessment will be conducted independently by two reviewers, focusing on study characteristics, intervention details and critical outcomes (reduction in depressive symptom severity and adverse effects). ResultsThe review will synthesize evidence on the effects and adaptability of theory-based interventions, highlighting the specific contributions of theoretical frameworks to intervention outcomes. Findings will be presented in tabular and narrative formats, identifying gaps and implications for clinical practice and future research. ConclusionThis systematic review will provide actionable insights into the design and implementation of theory-based interventions for managing mild to moderate depression. The findings aim to inform evidence-based guidelines for primary care integration, promoting accessible, scalable and effective mental health solutions globally.