非自杀性自伤行为(non-suicidal self-injury, 以下简称NSSI)是一种不以自杀为目的，直接地、蓄意伤害自己躯体组织的行为，是自杀尝试的重要风险因素。大学生自伤自杀问题一直是大学生心理危机干预关注的焦点，然而针对大学生NSSI现象深入的理论和实践干预研究还很有限，因此有必要回应实践需求和社会关切，深入研究大学生NSSI的发生机制和影响过程，提出有效的干预方案。

童年创伤是NSSI的一个独立且重要的远端风险因素，在有某种形式童年期创伤经历的儿童和青少年中，NSSI的检出率高达79%，然而童年创伤作为远端情境变量在大学阶段如何影响了NSSI的发生过程，对大学生NSSI的纵向影响和近端影响过程如何，该如何干预等问题的研究并不清楚。本研究综合以往文献，基于NSSI的获益和阻碍模型，结合人格心理学最新的人和情境互动等理论，构建了一个“情境(远端)→人×情境(近端)”理论框架，聚焦童年创伤对NSSI的影响机制问题，从特质和状态两个层面，探讨NSSI的个体内部风险因素(自我纠正和自我憎恨)以及保护因素(自我同情)在童年创伤与NSSI之间的中介作用机制，并且考察近端压力的调节效应，然后根据该结果进一步设计针对NSSI的干预方案并探讨干预效果，以期对大学生NSSI危机预防和干预提供实证基础。对应上述研究问题，本论文采用横断研究、纵向研究、日记研究、随机对照的干预研究等多种方法，从不同的角度进行了充分探讨。

研究1采用横断研究设计，以5550名普通大学生为研究对象，通过一个有调节的中介模型验证了童年创伤对NSSI的一般影响，结果发现童年创伤可以显著正向预测NSSI，特质水平的自我纠正、自我憎恨和自我同情同时在其中发挥部分中介作用，而压力积累风险和不同类型的压力可以调节童年创伤到NSSI的直接路径以及自我憎恨到NSSI的间接路径。

 研究2在研究1的基础上，通过1年的时间对1407名普通大学生进行了3次的追踪研究，采用纵向有调节的中介模型和潜增长曲线模型，探讨童年创伤对NSSI变化轨迹的作用机制。纵向有调节的中介模型发现，大学生NSSI的发生率在1年内呈下降趋势，童年创伤对一年后的T3NSSI有正向预测作用，特质水平的T2自我纠正和T2自我憎恨在童年创伤与T3NSSI之间发挥完全中介作用，而T2自我同情的中介作用不显著。T3压力风险和T3学习压力风险可以放大童年创伤对T3NSSI的正向预测作用，T3人际风险可以调节T2自我同情到T3NSSI的保护作用；潜增长曲线模型发现，童年创伤不仅可以正向预测NSSI的初始水平，还可以负向预测NSSI的下降速度。童年创伤对NSSI发展趋势的影响主要通过自我纠正/自我憎恨/自我同情截距路径的中介作用来体现，而不是斜率路径。自我纠正/自我憎恨初始水平的升高、自我同情初始水平的下降可以正向预测NSSI的初始水平，负向预测NSSI的下降速度，自我纠正/自我憎恨的变化速度正向预测着NSSI的变化速度，自我同情的变化速度则与NSSI的变化速度无关。1年内的压力水平不随时间发展发生变化，T1压力初始水平可以放大自我纠正/自我憎恨对NSSI的风险，减缓自我同情的保护作用。

研究3在前两个机制研究的基础上，聚焦有NSSI史的群体，采用经验取样的日记研究法，招募64名最近半年有NSSI史的大学生参与研究，进一步检验在日常压力变化下，状态水平的自我纠正、自我憎恨和自我同情在童年创伤对NSSI近端变化的作用机制。结果发现，只有被试间的平均状态自我憎恨可以在童年创伤与NSSI行为和NSSI冲动风险中发挥中介作用。每日压力水平可以放大被试间自我憎恨对NSSI行为和NSSI冲动的间接预测，对被试间自我纠正到NSSI行为/NSSI冲动中介路径有负向调节效应(边缘显著和显著)，自我纠正和自我憎恨表现出不同的功能模式。

 研究4基于前三个机制研究的基础上，结合辩证行为疗法的理念和技术，设计了一个改善自我批评(有建设性的自我纠正，降低自我憎恨)和发展自我同情(提供容错空间)的联合日记自助干预方案，共招募了97名非临床样本的大学生参与研究，通过一项随机对照研究探讨其对NSSI的有效性和作用机制。结果发现，该方案可以显著降低大学生NSSI行为的即时和延时风险，降低NSSI冲动的延时风险，能够显著降低NSSI史大学生的特质自我纠正和自我憎恨水平，提升自我同情水平。该方案能够显著地降低童年创伤对一个月后NSSI行为的延时风险，在特质水平上的作用机制主要是提高了自我同情水平在前，降低自我憎恨在后，而自我纠正的改变只在状态水平上发挥显著作用。

 综上，本文得出以下结论：

（1）童年创伤是NSSI行为稳定的远端风险因素，对NSSI行为的一般作用、发展趋势和短时变化均有预测作用，在横断和纵向水平上会因为近期压力的增加而放大风险，而在短时变化水平上则没有这种效应。

（2）在特质水平上，自我纠正和自我憎恨作为个体内部风险因素，自我同情作为保护因素是童年创伤到NSSI行为和冲动的重要中介机制，其中自我憎恨的作用具有最强的路径优势，且随着压力增加而放大风险，自我同情在长期水平上的保护作用需要人际压力的启动。

（3）在状态水平上，自我憎恨在童年创伤到NSSI行为和冲动之间同样表现出稳定的风险中介作用，而自我纠正在压力状态下表现出一定的情境适应性，自我同情表现出惰性。

（4）自我批评和自我同情联合日记自助干预方案可以显著降低NSSI风险，改善大学生的自我批评，提升自我同情，降低童年创伤对NSSI的延时风险。

本研究把自我批评和自我同情看作个体内部风险和保护因素，首次同时考虑其在童年创伤与NSSI之间的中介作用，以及压力情境的调节作用，研究结论进一步丰富和扩展了NSSI的获益和阻碍理论，从心身一体的视角对NSSI研究中远端因素和近端因素的互动机制提供了实证证据，增加了对不同功能自我批评和自我同情在NSSI中作用的理解，并在此基础上研发出对大学生NSSI有效的干预方案。对大学生心理健康筛查，NSSI干预实务工作和心理健康教育工作提供了可以借鉴的工作思路和有针对性的建议。

Non-suicidal self-injury (NSSI) involves the "direct, deliberate destruction of one’s own body tissue in the absence of suicidal intent" (Nock & Favazza, 2009), and it is an important risk factor for suicidal attempts. The issue of self-injuring and suicide attempting among university students has always been a focal point in psychological crisis intervention for university students. However, there is still limited theoretical and practical intervention for NSSI among college students. Therefore, it is necessary to respond to social concerns, conduct in-depth research on the mechanism and impact process of NSSI among college students and propose effective intervention program.

Childhood maltreatment is an independent and significant distal risk factor for NSSI. Among children and adolescents who have experienced some form of childhood maltreatment, the detection rate of NSSI can reach up to 79%. However, it is unclear how childhood maltreatment experiences affect the mechanism and longitudinal process of NSSI in college students. This study integrated previous literature, and to meet the shortcomings of the previous studies, a moderated mediation model of " situation (distal) - person × situation (proximal)" was proposed based on benefits and barriers models, and combined the latest progress in personality psychology “person × situation interactionism perspective”, focusing on the mechanisms through which childhood maltreatment affects NSSI. From both trait and state perspectives, this study explores the mediating role of individual internal risk factors (self-criticism: distinguish inadequate-self and hated-self) as well as protective factor (self-compassion) between childhood maltreatment and NSSI. Additionally, it examines the moderating effect of proximal stressors. Based on these results, intervention programs targeting NSSI ware further designed to explore their effectiveness with the aim of providing empirical evidence for crisis prevention and intervention among college students facing NSSI. To address these research questions mentioned above, this research employed various methods including cross-sectional study, longitudinal study, diary study of empirical sampling, and randomized controlled intervention study to thoroughly investigate from different angles.

Study 1 verified the impact of childhood maltreatment on NSSI using a moderated mediation model through a cross-sectional study with 5550 college students. The results showed that childhood maltreatment can significantly positively predict NSSI, and inadequate-self, hated-self and self-compassion played a partial mediating role. Stress events can moderate both the direct path and the indirect path of hated self to NSSI.

Building upon Study 1, Study 2 conducted a three-wave longitudinal study over one year with 1407 college students. Both longitudinal moderated mediation model and Latent Growth Curve Model(LGCM) were utilized to examine the stability of Study 1's model across time and to explore the mechanism of childhood maltreatment on the trajectory of NSSI change. The results showed that the incidence of NSSI was decreasing within one year. Childhood maltreatment positively predicted T3 NSSI after one year, while T2 inadequate-self and T2 hated-self fully mediated between childhood maltreatment and T3 NSSI. However, the mediating effect of T2 self-compassion was not significant. Furthermore, T3 stress accumulation risk and T3 learning stress can amplify the positive predictive effect of childhood maltreatment on T3 NSSI, while T3 interpersonal stress can moderate T2 self-compassion to the indirect protective effect of T3 NSSI. In addition, through the results of LGCM, it is found that childhood maltreatment can not only positively predict the intercept of NSSI, but also negatively predict the slope of NSSI. The increase of the intercept of inadequate-self and hated-self and the decrease of self-compassion intercept can positively predict the intercept of NSSI and negatively predict the slope of NSSI. The influence of childhood maltreatment on NSSI changes is mainly mediated by the intercept path of inadequate-self/hated-self/self-compassion, but not the slope path. The slope of inadequate-self and hated-self can positively predict the slope of NSSI. The slope of self-compassion was independent of the slope of NSSI. Stressful events within one year do not change over time, and T1 stress levels can amplify the risk of inadequate-self and hated-self for NSSI, slowing the protective effects of self-compassion.

Based on the previous two mechanism studies, In study 3, Employing an experience-sampling diary method, we recruited 64 college students who had engaged in NSSI within the past six months to further examine the mechanisms through which childhood trauma influences proximal changes in NSSI behavior under daily stress exposure in the NSSI ecological environment of college students. The results showed that only the average state hated-self of between-level can mediate the childhood maltreatment on NSSI behavior and NSSI urge. And the increase of daily stress exposure can amplify the prediction of between level hated-self on NSSI urge or NSSI behavior, and have negative moderated effects on the mediation path from inadequate-self to NSSI behavior/NSSI urge (marginal and significant).

In Study 4, A combined diary writing intervention, based on DBT concepts and techniques, was developed to reduce self-hatred (proposing constructive self-criticism) and develop self-compassion (providing fault-tolerant space). The effectiveness and mechanism of action on NSSI was explored through a randomized controlled study involving the recruitment of 97 non-clinical undergraduate students. Results showed that NSSI behavior and NSSI urge were significantly reduced in college students with a history of NSSI after the intervention and 1 month later. The levels of trait inadequate-self and hated-self were significantly reduced, and self-compassion was significantly increased. The protocol reduces the risk of childhood maltreatment on NSSI after 1 month. The mechanism of the program at the trait level is mainly to improve the level of self-compassion in the first place, and reduce hated-self in the second, while inadequate-self only plays a significant role at the state level.

In summary, this paper draws the following conclusions:

(1) childhood maltreatment serves as a stable distal risk factor for NSSI has a positive predictive effect on the long-term, development trend and short-term change of NSSI behavior, and will amplify the risk associated with recent stress at the long-term level, while not significantly impacting short-term changes in NSSI behavior.

(2) At the trait level, inadequate-self and hated-self act as risk factors and self-compassion acts as protective factors are important influencing mechanisms in childhood maltreatment on NSSI behaviors. Among these factors, hated-self exhibits the strongest path advantage. Furthermore, increased stress intensifies the association between hated-self and NSSI, while interpersonal stress moderates self-compassion's protective role against NSSI.

(3) At the state level, hated-self also exhibited stable risk, while inadequate-self demonstrated some situation adaptability under stress, and self-compassion displayed inertia.

(4) Self-criticism and self-compassion combined diary-based intervention program can significantly reduce the risk of NSSI, improve self-criticism among college students, enhance self-compassion, and decrease the delayed risk of childhood maltreatment on NSSI.

    This study considers self-criticism and self-compassion as interpersonal risk and resilience factors within individuals, and for the first time simultaneously examining their mediating role between childhood maltreatment and NSSI by the moderating of the stressful situations. The research findings enrich and extend the theory of the benefit and barrier model of NSSI by providing empirical evidence for the interaction mechanism of distal and proximal factors in NSSI research from a mind-body perspective. Furthermore, it enhances our understanding of different functional aspects of self-criticism and self-compassion in relation to NSSI while proposing an effective intervention program for addressing this issue. Additionally, some suggestions are provided for mental health screening among college students as well as interventions targeting NSSI prevention and mental health education.