Non-suicidal self-injury (NSSI) in young adults is recognized as a major public health concern. Some studies have identified cumulative childhood maltreatment (CCM) as a significant vulnerability factor for NSSI, although the nature of this association remains unclear. Specifically, some theorists have investigated the role of perceived social support (PSS), considered an important factor closely associated with both CCM and NSSI. The aim of the current study was to simultaneously investigate the potential mediating and moderating role of PSS from family and friends in the association between CCM and NSSI in a university student sample. Participants were 474 students (73.4% female; M_age = 21.61, SD = 1.92) attending a state university in southern Italy (Sicily) who completed self-report questionnaires regarding childhood trauma, non-suicidal self-harming behaviors, and PSS. The mediation model showed that CCM was significantly and positively linked to NSSI through perceived support from family, so that the higher the CCM, the lower the perceived support from family and, consequently, the higher the presence of NSSI behaviors. Moreover, the moderating model indicated that perceived support from friends buffered the relation between CCM and NSSI. These findings expand our understanding of the role of PSS in the relation between CCM and NSSI. Specifically, the perception of family support may be affected by early maltreatment experiences, increasing the risk of NSSI (mediation), whereas it seems that perceived friends support operates as a stress buffer, mitigating the deleterious effects of CCM on NSSI (moderation). Methodological limitations and clinical implications of the study are discussed.

年轻人的非自杀性自伤 (NSSI) 被认为是一个主要的公共卫生问题。一些研究已将累积儿童虐待 (CCM) 确定为 NSSI 的重要脆弱性因素，尽管这种关联的性质尚不清楚。具体而言，一些理论家研究了感知社会支持 (PSS) 的作用，被认为是与 CCM 和 NSSI 密切相关的重要因素。本研究的目的是同时调查来自家人和朋友的 PSS 在大学生样本中 CCM 和 NSSI 之间的关联中的潜在中介和调节作用。参与者为 474 名学生（73.4% 为女性；M_年龄 = 21.61，SD = 1.92）就读于意大利南部（西西里岛）的一所州立大学，他们完成了关于童年创伤、非自杀性自我伤害行为和 PSS 的自我报告问卷。中介模型表明，CCM 通过感知家庭支持与 NSSI 显着正相关，因此 CCM 越高，感知家庭支持越低，因此 NSSI 行为的存在程度越高。此外，调节模型表明朋友的感知支持缓冲了 CCM 和 NSSI 之间的关系。这些发现扩展了我们对 PSS 在 CCM 和 NSSI 之间关系中的作用的理解。具体而言，家庭支持的感知可能会受​​到早期虐待经历的影响，增加 NSSI（调解）的风险，而感知到的朋友支持似乎起到了压力缓冲的作用，减轻了 CCM 对 NSSI 的有害影响（适度）。讨论了该研究的方法学局限性和临床意义。