Suicide has become a public health problem in many countries, and it is the fourth leading cause of death among young people aged 15–29 years globally (WHO, 2019). Self-harm (intentionally self-inflicted physically harmful act, regardless of suicidal intent) is even more common, with tens of millions of individuals affected each year (Knipe et al., 2022). Prevalence estimates of suicide and non-suicidal self-injury (NSSI) in the college student population are consistently high, particularly in the early stages of entry to university (Gandhi et al., 2018; Mortier et al., 2018). Increasingly competitive and stressful student life, lessened parental oversight when leaving the family home for the first time, and easier access to alcohol and other substances are among the many factors that correlate with high risks of mental health problems including NSSI and suicide (O'Neill et al., 2018). Therefore, it is vital to explore correlates that may be associated with, and might ultimately contribute to, NSSI and suicide in college students, which could inform appropriate interventions before crises situations emerge.

Previous research has made considerable progress in understanding the correlates and risk factors of NSSI and suicide in young people (Carballo et al., 2020; Hawton et al., 2012). In this study, we focus on two main factors, (1) psychological and psychiatric factors and (2) psychosocial factors related to family and peer problems, as they are modifiable and thus can be targeted in prevention strategies. As for the psychiatric factors, depression is the most commonly studied risk factor and is consistently integrated into structured suicide-risk assessments by many national and international organizations (Ribeiro et al., 2018). In addition, psychotic-like experiences (PLE) have been found to be associated with NSSI, suicidal ideation as well as suicidal attempts, even after adjusting for related psychopathology such as depression (Honings et al., 2016). Other risk behaviors include alcohol use (Chikritzhs and Livingston, 2021), smoking (Hawton et al., 2012), and Internet addiction (Marchant et al., 2017).

When considering social factors, family-level variables are particularly important for adolescents and young adults. Childhood maltreatment (e.g., emotional abuse, physical abuse, neglect), parental separation or divorce, household financial difficulties are all well-recognized correlates of NSSI and suicide (Sahle et al., 2022). Apart from family dysfunction, peer conflict such as being bullied is also associated with a range of mental health problems (Gini and Pozzoli, 2009). With the advent of electronic communication, cyberbullying has emerged, and an estimated 15 %–35 % of young people have been victims of cyberbullying (Hinduja and Patchin, 2010). Cyberbullying involvement may have similar or even more severe negative effects than traditional bullying (John et al., 2018). Therefore, we also included cyberbullying victimization as a potential risk factor. Finally, in the context of resilience, social support acts as a protective factor buffering the pathway from negative life events to NSSI and suicide (Tham et al., 2020).

Despite the recognition of correlates and risk factors, our ability to predict NSSI and suicide has not been muchly improved (Franklin et al., 2017). It is also unclear how different factors interact with each other, and which factors may directly or indirectly affect NSSI and suicidal thoughts and behaviors. Network analysis is therefore particularly suited to explore the complex interplay and unique contribution of risk and resilience factors for NSSI and suicide (Borsboom and Cramer, 2013). Extending traditional methods such as regression analysis, network approach can quantify and visually display the potential relationship between a wide range of different symptoms and risk factors while controlling for other variables within the network (Borsboom, 2017). Moreover, node centrality is informative to highlight which nodes are most important to the maintenance of the network, potentially giving insight into targets for treatment (Borsboom, 2017). To date, a few studies have used network analysis to decode the interrelationship between known correlates of suicide/self-harm among veterans (Graziano et al., 2021; Simons et al., 2020), patients with major depression (Núñez et al., 2020), and children and adolescents (Hinze et al., 2022). However, little is known about the structure of “risk networks” for NSSI and suicide in young people and college students.

This exploratory study was designed to examine a network of NSSI, suicide and their psychological and psychosocial correlates in a sample of Chinese college students. Results may delineate the interrelationship between different factors, provide insights into which factors are most important correlates of NSSI and suicide, and thus contribute to our understanding of suicidal risk assessment and interventions in young people.