Intervention Measures of Non-suicidal Self-harm Behaviors among Adolescents: A Scoping Review

This scoping review aims to systematically map and synthesise the existing evidence on non‑pharmacological interventions for non‑suicidal self‑injury (NSSI) among adolescents. NSSI, defined as deliberate and direct self‑inflicted damage to body tissue without suicidal intent, is closely associated with emotional distress, psychiatric comorbidity and an increased risk of subsequent suicidal behaviour. A variety of psychological and psychosocial interventions have been developed, but they differ widely in their theoretical foundations, target populations, delivery formats and outcome measures. At present, there is no comprehensive overview that organises these interventions and their components in a way that can inform clinical practice and future research. Following the Joanna Briggs Institute (JBI) methodology for scoping reviews and the PCC (Participants–Concept–Context) framework, we will focus on: (P) adolescents aged 10–19 years, irrespective of specific diagnoses (e.g. depression with NSSI, anxiety with NSSI, or adolescents identified primarily on the basis of NSSI behaviour); (C) non‑pharmacological interventions that are explicitly applied to adolescents with NSSI or non‑suicidal self‑harm, including details of intervention format, combinations of components, theoretical underpinnings, mechanisms of action, core elements, implementation processes, intensity and duration, and reported effects; and (C) any setting in which such interventions are delivered, including but not limited to general hospitals, psychiatric services, community health centres, schools and family/home environments. We will conduct a comprehensive search of both international and Chinese databases, including Sinomed, PubMed, MEDLINE, APA PsycArticles, CINAHL, Web of Science, the Cochrane Library, CNKI, Wanfang and VIP. Search strategies will combine controlled vocabulary and free‑text terms related to adolescents, NSSI/non‑suicidal self‑harm and interventions. We will include quantitative intervention studies involving adolescents with NSSI that report primary data; and we will exclude dissertations, conference abstracts, protocols, non‑full‑text reports, single‑case reports, narrative reviews and purely qualitative studies. No restrictions will be placed on geographic region or publication country. Study selection will be performed independently by at least two reviewers. For each included study we will chart two main groups of information. First, we will extract bibliographic and methodological characteristics to build a study‑characteristics table (e.g. title, authors, country, year, study design, study objectives, sample size, age, sex, health status and setting). Second, we will extract detailed intervention‑related information to build an intervention‑content table, including the stated theoretical or conceptual model (where reported), intervention type and components, delivery format, provider, frequency and duration, adherence or compliance, comparison/usual‑care conditions, reported outcomes or evaluation measures, timing of outcome assessments and main findings. Data will be summarised in these structured tables and accompanying narrative synthesis to highlight patterns across interventions, populations, settings and outcomes. The expected outputs of this project are: (1) a study‑characteristics table that provides an overview of the existing evidence base on non‑pharmacological interventions for adolescent NSSI; (2) an intervention‑content table that systematically describes intervention types, core components, delivery models and reported outcomes; and (3) identification of key gaps in the current literature, such as understudied populations, neglected intervention components, limited follow‑up or methodological limitations. These findings are intended to guide clinicians, nurses, psychologists, school staff and researchers in designing, adapting and evaluating future interventions, and to inform subsequent effectiveness‑focused systematic reviews and trials.