METHODS: The review followed the scoping methodology of Arksey and O\'Malley from 2005, updated by Levac and colleagues in 2010, involving five stages: (1) identifying the research question, (2) identifying relevant studies, (3) study selection, (4) charting the data, and (5) collating, summarizing and reporting the results.
RESULTS: Nineteen studies were included. The following themes on adolescents` voices regarding self-engagement in mental health treatment were identified: (1) the therapeutic alliance, (2) the need for active engagement in treatment, (3) different experiences due to time of data collection, (4) treatment context and healthcare system, and (5) adolescent-caregiver interaction.
CONCLUSIONS: Adolescents\' understanding of self-engagement was multilevel and comprehensive, including individual, contextual and relational factors. A strong therapeutic alliance with healthcare providers, and a need to be actively engaged in treatment were highlighted. To succeed in strengthening PCC in mental healthcare for adolescents, health professionals must take this complex understanding into consideration, as treatment without adolescents` self-engagement may worsen their clinical outcomes. Future research should explore specific PCC interventions and incorporate diverse methodologies in various clinical contexts. Additionally, insights from healthcare providers and caregivers on self-engagement in mental health treatment will complement these findings.