Journal of Childhood

Introduction
Research findings show that some adolescents express their psychological distress and internal contradictions through behaviors, such as self-harm to relieve negative emotions. Although researchers have increasingly focused on intentional self-harm in adolescents in recent years, information regarding this harmful behavior remains limited. There is also no accurate information about the prevalence of self-harm behaviors in non-clinical samples (Kentup et al., 2021). Given the importance of this issue, the impact of various factors on adolescent self-harm, particularly in delinquent adolescents, is widely acknowledged. Therefore, the use of prevention and treatment methods is an undeniable necessity. Therefore, this study aimed to compare the effect of Islamic quality of life education and dialectical behavior therapy skills training on self-harm behaviors in delinquent adolescents..
Research Methods
This research conducted as a quasi-experimental study employing a pre-test, post-test, and follow-up design, involving two intervention groups and one control group.  It is a quantitative study in terms of research approach.  The population for this study comprised all adolescents residing in the Zahedan Correctional Center in 2024. Using the purposive sampling method and employing the Power*G software (with an effect size of 0.15) to determine an appropriate sample size for quasi-experimental studies, the sample size for the present study was set at 60 adolescents.
The measurement tool used in this study was the Klonsky and Glenn Self-Harm Questionnaire. The first intervention group received the Islamic quality of life improvement training course, and the second intervention group received dialectical behavior therapy skills training. These interventions were delivered in 8 group sessions, each lasting 60 minutes (one session per week).  The control group was placed on a waiting list. Multivariate analysis of covariance (MANCOVA) was used to analyze the research data. 
Results
The results of Table 6 indicate that, based on the significance levels (p-values) for all within-group test statistics, the null hypothesis was rejected. Therefore, it can be concluded that the effect of the independent factor (time: pre-test, post-test, and follow-up) on the dependent variables was statistically significant. Table 1 thus presents the results of repeated measures ANOVA regarding the effect of time on the components of self-injurious behaviors among delinquent adolescents. 
Table 2 provides the results of Duncan’s post hoc test for comparing the mean scores of the three groups (Intervention 1, Intervention 2, and Control) across the three measurement stages. 
The results of Table 2 demonstrate that self-injurious behaviors differ significantly across time within the three subgroups. The lowest mean scores were observed in the post-test condition for both intrapersonal functions (M=5.3) and interpersonal functions (M=5.4) following the dialectical behavior therapy intervention.  Similarly, the post-test of the Quality of Life intervention showed the lowest means for interpersonal functions (M=7.4) and intrapersonal functions (M=8.0). Additionally, during the follow-up stage, the mean scores of the intervention groups showed minimal change, while the control group’s mean scores increased. In other words, both dialectical behavior therapy and quality of life enhancement interventions contributed to a reduction in self-injurious behaviors. 
The findings in Table 3 reveal that both dialectical behavior therapy and quality of life enhancement interventions significantly improved intrapersonal (F=4.893, P=0.015) and interpersonal (F=21.303, P<0.001) functions at the post-test stage. Accordingly, the study hypothesis was confirmed. 


Conclusion
Overall, the findings of the present study demonstrated that both the quality of life enhancement intervention and dialectical behavior therapy contribute to the prevention of self-injurious behaviors among delinquent adolescents. Given the prevalence of self-injurious behaviors in this population, understanding the benefits and challenges of various therapeutic approaches is of considerable importance. It appears that integrating Islamic-based quality of life training with dialectical behavior therapy skills may serve as an effective clinical intervention. Such integration, alongside other evidence-based practices, can contribute to the improvement and optimization of mental health interventions for delinquent adolescents by combining the strengths of Islamic perspectives on quality of life with empirically validated therapeutic methods. 
Like other studies, this research also faced several limitations. First, self-report instruments were employed, which may have influenced the accuracy of the findings. Second, the study sample consisted exclusively of delinquent adolescents in Zahedan, thereby limiting the generalizability of the results to other regions of the country. 
Based on these findings, several practical and research-oriented recommendations are suggested. Considering the effectiveness of both approaches, it is recommended that educational workshops on Islamic-based quality of life training and dialectical behavior therapy skills be implemented in correctional centers, special schools, and counseling institutions for delinquent adolescents. Such programs may help reduce self-injurious behaviors and enhance intrapersonal and interpersonal functioning. Furthermore, future studies with larger and more diverse samples (including both male and female adolescents from different cultural contexts) are encouraged to enhance the generalizability of findings and to explore possible differences in the effectiveness of the two interventions. 

Ethical Considerations
Compliance with ethical guidelines
This article was approved  by the research ethices committee of Farhangian University, Tehran (code: 273/8/1908/403). All ethical principles were considered in this article. The participants were informed of the purpose of the research and its implementation stages. They were also assured about the confidentiality of their information and were free to leave the study whenever they wished, and if desired, the research results would be available to them.
Funding
This research did not receive any grant from funding agencies in the public, commercial, or non-profit sectors. 
Authors contributions
All authors contributed equally to the conception and design of the study, data collection and analysis, interpretation of the results, and drafting of the manuscript. Each author approved the final version of the manuscript for submission.
Conflicts of interest
The authors declared no conflicts of interest.
Acknowledgements
The authors extend their sincere gratitude and appreciation to the exemplary individuals, the institutions that issued the necessary permits, and the supervisors and consultants who provided invaluable assistance in conducting this study.