Introduction
Adolescence is a sensitive period due to physical and psychological changes. In this period, serious damages may occur that can lead to behavioral problems such as self-harm [1]. The self-injury behaviors are defined as the behaviors leading to deliberate causing of injury to own body skin tissues. It also includes the behaviors causing indirect damage to the body, and is seen among adolescents at different cultures [2]. 
Emotional child abuse is defined as a repetitive pattern of behaviors that damage a child; these repetitive patterns induce the children that they are worthless, unloved, and unwanted [3]. The experience of emotional abuse in childhood is related to self-injury behaviors [4]. Therefore, recognition of emotional abuse in childhood as a causative agent is a major step towards the progress of psychology and preventive psychiatry based on science [5]. In adolescents with various psychiatric diseases, the most important factor in predicting self-injury behaviors is the limited access to emotion regulation strategies [6]. The problem in emotional regulation makes a person unable to use effective strategies for managing emotions. Several studies have reported emotional dysregulation as one of the most common causes of self-injury behaviors in adolescents [7]. The present study aims to investigate the mediating role of emotion regulation strategies in the relationship between emotional child abuse and self-injury behaviors in female adolescents.
Methods
This is an analytical cross-sectional study . The study population consisted of all high school female students in Rasht, Iran. Of these, 200 were selected using a convenience sampling method. The criteria for entering the study included the access to internet, age 15-18 years, willingness to participate in the study, while the exit criteria were unwillingness to cooperate and return of incomplete questionnaires. Data collection tools were the self-harm inventory (SHI), childhood trauma questionnaire (CTQ), and emotion regulation questionnaire (ERQ). The collected data were analyzed using structural equation modeling (SEM) and path analysis in SPSS v. 23 and Amos v. 26.
Results
The results of direct relationships between the study variables in the proposed model showed a significant positive relationship between emotional abuse in childhood and self-injury behaviors. There was a significant negative and positive relationship between emotional abuse in childhood and reappraisal (β=-0.32, P<0.001) and suppression (β=0.47, P<0.001) domains, respectively. Moreover, reappraisal (β=-0.40, P<0.001) and suppression (β=0.30, P<0.001) domains had significant negative and positive relationship with self-injury behaviors, respectively. The bootstrap test in Preacher & Hayes macro program [8] was used to examine the mediating roles. The results showed that the indirect effect of emotional abuse in childhood on self-injury behaviors through reappraisal and suppression domains was statistically significant and equal to 0.128 and 0.141, respectively. The SEM model had a good fit (Figure 1). Discussion
The purpose of this study was to investigate the mediating role of emotion regulation strategies in the relationship between emotional abuse in childhood and self-injury behaviors in female adolescents. The results showed that the direct and indirect effects of variables on each other were significant and the research model had a good fit. Based on the findings of this study, emotional regulation strategies have important role in the relationship between emotional abuse in childhood and self-injury behaviors in female adolescents; therefore, the development of emotional regulation training programs for female adolescents can help them face high-risk behaviors, including self-injury.

Ethical Considerations
Compliance with ethical guidelines
Ethical considerations of this research included informed consent to participate in the research, emphasizing the confidentiality of information and avoiding harming the participants. They were allowed to withdraw from the study at any time. This study has been approved by the Ethics Committee of Guilan University of Medical Sciences with the code of ethics (IR.GUMS.REC.1400.019).

Funding
This research is taken from the master's thesis of Fatemeh Shahnazdoost, Department of Psychology, Faculty of Educational Sciences and Psychology, University of Mohaghegh Ardabili, and no funding was received from any organization.

Authors' contributions
The authors had equal contribution to the preparation of the manuscript.

Conflicts of interest
The authors declared no conflict of interest.

Acknowledgements
The authors appreciate and thank all the students, school officials and people who helped the authors in completing the research questionnaire and other stages of the implementation of this study.
 

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