Non-suicidal self-injury behaviours among adolescents in Beijing: protocol for an epidemiological and qualitative...

Non-suicidal self-injurious behaviour (NSSI) is defined as purposeful self-injury without the intention to die. NSSI has become an important threat to public health among teenagers globally, imposing considerable costs on individuals, families and society. It reflects poor emotional regulation and serves as an early warning sign for suicidal ideation and behaviour. The purpose of this study is to look at the prevalence of NSSI and the risk factors related to it in Beijing's adolescent population.

Epidemiological surveys and qualitative interviews will both be used in this study. First, a cross-sectional epidemiological survey with stratified sampling will assess the prevalence, risk factors and variables associated with NSSI among adolescents in Beijing. The survey will include a sample size of at least 1415 adolescents. The significance of emotional control, social support and mental health in NSSI conduct will then be investigated through qualitative interviews. This part of the study will use a phenomenological qualitative research approach, with the sample size determined by data saturation, typically around 10 participants, but flexible due to the large sample from the epidemiological survey. In order to investigate the prevalence of NSSI, statistical analysis of correlation, descriptive statistics and regression analysis with multiple variables will be used to analyse the survey data using SPSS V.27.0 and Excel 2003. NVivo V.12 software will be used to code the qualitative data, and thematic analysis and word frequency will be used to find connections between the various NSSI experiences.

The Guang'anmen Hospital Ethics Committee of the China Academy of Chinese Medical Sciences has given its approval to the project (no. 2023-259-KY). Participants will provide both verbal and written informed consent prior to participation, with legal guardians signing for the qualitative part of the study. Participants will be informed of their right to withdraw from the study at any time without affecting their clinical care. Results will be shared through academic journals, conferences and public health platforms to raise awareness of NSSI and inform related policy development.

ChiCTR2400085968.