Effectiveness of Behavior Change–Based Interventions in Promoting Mental Health: A Behavioral Science Approach

Abstract

This study aimed to explain service users’ perceptions and lived experiences of the mechanisms, conditions, and outcomes through which behavior change–based interventions contribute to mental health promotion. A qualitative design using thematic analysis was employed. Participants were 24 adults living in Tehran who had previously attended at least one psychological or health-oriented intervention incorporating behavior change strategies. Purposive maximum-variation sampling was applied to obtain diversity in age, gender, education, marital status, and type of intervention. Recruitment and interviewing continued until theoretical and thematic saturation was achieved. Data were collected through in-depth semi-structured interviews lasting approximately 55 minutes on average. All interviews were audio-recorded with permission, transcribed verbatim, and analyzed using thematic analysis supported by NVivo software. Credibility and trustworthiness were enhanced through participant validation, independent coding, constant comparison, peer review, reflexive documentation, and maintenance of an audit trail. Analysis generated 486 initial codes, 41 subcategories, and five main categories: “from awareness to regaining a sense of control,” “small, specific, and sustainable changes,” “reorganizing lifestyle as a foundation for mental health,” “the role of the therapeutic relationship, social support, and facilitating environments,” and “personalization, feedback, and lapse management.” Participants described self-monitoring, gradual goal setting, action planning, behavioral activation, sleep regulation, physical activity, reduction of avoidance, supportive relationships, and professional feedback as important mechanisms associated with greater self-efficacy, emotional stability, daily functioning, and engagement in meaningful activities. The perceived effectiveness of behavior change interventions was not attributed merely to information provision or professional advice. Rather, it emerged from the interaction of psychological capability, environmental opportunity, autonomous motivation, therapeutic collaboration, and continued support. Flexible, participatory, context-sensitive interventions based on manageable behavioral steps appeared more likely to produce sustainable improvements. Mental health programs should therefore move beyond uniform prescriptive approaches and systematically assess behavioral barriers, match intervention techniques to individual needs, facilitate supportive environments, monitor progress, and normalize lapse management as part of long-term change.