Background Non-suicidal self-injury (NSSI) is a risk factor for suicide. This study aimed to investigate the prevalence of NSSI and professional psychological help-seeking status and influencing factors among left-behind children (LBC) in China. Methods We implemented a population-based cross-sectional study in participants aged 10–18 years. Sociodemographic characteristics, NSSI, help-seeking status and coping style were measured by self-reported questionnaires. A total of 16,866 valid questionnaires were collected, including 6096 LBC. Binary logistic regression models were used to analyze the factors influencing NSSI and professional psychological help-seeking. Results The incidence of NSSI among LBC was 4.6%, significantly higher than that of non-left-behind children (NLBC). This incidence was higher among girls. Moreover, 53.9% of LBC with NSSI did not receive any treatment and only 22.0% sought professional psychological help. LBC often adopt emotion-oriented coping styles, specifically, those with NSSI. LBC with NSSI who seek professional help tend to adopt problem-oriented coping styles. Logistic regression analysis revealed that girls, learning stage, single-parent, remarried families, patience, and emotional venting were risk factors for NSSI in LBC, while problem-solving and social support seeking were protective factors. Moreover, problem-solving was also a predictor for seeking professional psychological help, patience will prevent it. Limitations This was an online survey. Conclusions The prevalence of NSSI in LBC is high. Gender, grade, family structure, and coping style affect the occurrence of NSSI among LBC. Only a few LBC with NSSI seek professional psychological help, while the coping style will affect the help-seeking behavior.

Background and Objectives: The analysis of clustering characteristics of disease risk factors makes for the formulation of corresponding prevention and control policies, but the risk factors for non-suicidal self-injury (NSSI) behaviors in adolescents is not covered, so this study is intended to explore the clustering characteristics of risk factors for NSSI behaviors in adolescents in the multi-center primary and secondary schools in western China.Methods: Utilising stratified and cluster sampling methods, a total of 13,784 primary and secondary school students who met the research standards were randomly selected as the survey subjects in year 2020, and the clustering situation of the seven risk factors (depression, anxiety, stress, low social support, tolerance, avoidance, and emotional venting) among the students was analyzed. The characteristics of the respondents with high clustering degree of risk factors for NSSI behaviors were also identified with the hierarchical logistic regression analysis. Results: 4.2% of the adolescents in western China were detected with NSSI behaviors in the past year; the risk factors were grouped into 4 clusters, ranging from level 0 to level 3, with each level including 7692 (55.8%), 3847 (27.9 %), 1303 (9.5%) and 941 (6.8%) of the survey subjects, respectively. The results of the Cochran-Armitage trend test analysis showed that there existed a linear trend between the clustering degree of risk factors and the detection rate of NSSI behaviors (P<0.000); according to the hierarchical logistic regression analysis, the clustering degree of risk factors for NSSI behaviors was higher in the adolescents whose parents divorced and remarried 1.22 (0.021~0.379) and whose fathers received only primary school education or below 1.23 (0.004~0.403). By contrats, the degree was lower in the adolescents who are male 0.93 (-0.133~-0.003) and had never attended boarding school 0.83 (-0.285~-0.094), whose parents were not divorced 0.80 (-0.367~-0.072), and whose fathers were farmers 0.99 (-0.136~0.123). Conclusion: The risk factors for NSSI behaviors in adolescents are in clusters. As the risk factors continue to cluster, NSSI behaviors can be detected more easily in adolescents. With respect to the endeavors to prevent and control NSSI behaviors in adolescents, more attention should be focused on the mental health of the adolescents who are female and attend boarding schools, whose parents have broken marriages, and whose fathers have low literacy.

Background and objectives: The analysis of clustering characteristics of disease risk factors makes for the formulation of corresponding prevention and control policies, but the risk factors for non-suicidal self-injury (NSSI) behaviors in adolescents is not covered, so this study is intended to explore the clustering characteristics of risk factors for NSSI behaviors in adolescents in the multi-center primary and secondary schools in western China. Methods: Utilizing stratified and cluster sampling methods, a total of 13,784 primary and secondary school students who met the research standards were randomly selected as the survey subjects from January 2020 to January 2021, and the clustering situation of the seven risk factors (depression, anxiety, stress, low social support, tolerance, avoidance, and emotional venting) among the students was analyzed. The characteristics of the respondents with a high clustering degree of risk factors for NSSI behaviors were also identified with the hierarchical logistic regression analysis. Results: 4.2% of the adolescents in western China were detected with NSSI behaviors in the past year; the risk factors were grouped into 4 clusters, ranging from level 0 to level 3, with each level including 7692 (55.8%), 3847 (27.9 %), 1303 (9.5%) and 941 (6.8%) of the survey subjects, respectively. The results of the Cochran-Armitage trend test analysis showed that there existed a linear trend between the clustering degree of risk factors and the detection rate of NSSI behaviors (P<0.000); according to the hierarchical Logistic regression analysis, the clustering degree of risk factors for NSSI behaviors was higher in the adolescents whose parents divorced and remarried 1.21（0.016~0.373）and whose fathers received only primary school education or below 1.23（0.005~0.404）. By contrast, the degree was lower in the adolescents who are male 0.93（-0.132~-0.003） and had never attended boarding school 0.83（-0.286~-0.096）, whose parents were not divorced 0.80（-0.367~-0.072）, and whose fathers were farmers 0.87（-0.271~0.006）. Conclusion: The risk factors for NSSI behaviors in adolescents are in clusters. As the risk factors continue to cluster, NSSI behaviors can be detected more easily in adolescents. With respect to the endeavors to prevent and control NSSI behaviors in adolescents, more attention should be focused on the mental health of the adolescents who are female and attend boarding schools, whose parents have broken marriages, and whose fathers have low literacy.