The prevalence of non-suicidal self-injury (NSSI) among adolescents underscores the importance of understanding the complex factors that drive this behaviour. Framed within broader constructs of emotional regulation theories, alexithymia and peer victimisation are thought to interact to influence NSSI behaviours.

This research addresses whether alexithymia and peer victimisation serve as risk factors for NSSI and, if so, how these factors interact with each other.

This quantitative study analysed data from 605 adolescents, using a range of validated self-report measures including the Toronto Alexithymia Scale. Statistical analyses including one-way analysis of variance, multiple regression and structural equation modelling were employed to scrutinise the relationships among the variables.

Alexithymia and peer victimisation significantly predicted NSSI behaviours. Specifically, the ‘difficulty in identifying feelings’ subscale of alexithymia emerged as a noteworthy predictor of NSSI (P < 0.001). Peer victimisation mediated the relationship between alexithymia and NSSI, explaining approximately 24.50% of alexithymia's total effect on NSSI. In addition, age was a significant predictor of NSSI, but gender and education years were not (P > 0.05). These relationships were found to be invariant across genders.

This study enriches our understanding of the interplay between alexithymia, peer victimisation and NSSI, particularly within the Chinese context. Its findings have significant implications for a rethinking of alexithymia's theoretical construct and interventions targeting emotional literacy and peer dynamics among adolescents. Future research could benefit from a longitudinal design to establish causality.

Adolescence is a pivotal stage vulnerable to mental health problems such as anxiety and depression. Although self-acceptance and social comparison are known to affect adolescent mental health, their interactive and moderating roles are not fully understood.

To explore the role of self-acceptance, social comparison and attributional style in predicting these mental health outcomes among adolescents in clinical settings.

A cross-sectional study was conducted on a sample of 242 adolescents. Participants completed measures assessing self-acceptance, social comparison, attributional style and mental health outcomes (depression and anxiety). Mediation models and multi-group analysis were used to examine the relationships among these variables.

Our findings demonstrated a significant relationship between self-acceptance, social comparison, depression and anxiety (rs = 0.32–0.88). Specifically, lower self-acceptance and higher social comparison were associated with higher levels of depression and anxiety. Additionally, individuals with external attributional tendencies reported higher depression (Cohen's d = 0.61) and anxiety (d = 0.58) compared with those with internal tendencies. Mediation modelling showed that social comparison is a mediator between self-acceptance and depression (effect size −0.04, 95% CI −0.08 to −0.01) and anxiety (effect size −0.06, 95% CI −0.10 to −0.02). Crucially, multi-group analysis showed that the impact of social comparison on mental health outcomes varied significantly based on attributional style.

These findings underscore the importance of considering self-acceptance, social comparison and attributional style in understanding and addressing mental health challenges during adolescence. This could inform the development of targeted interventions to promote mental health and well-being among adolescents. However, further research is needed to confirm these findings in diverse populations and to explore the underlying mechanisms in greater detail.