自傷行為與自殺危險性的階層預測模式－－三元模式的延伸

Applying the Tripartite Model to the Link between Non-Suicidal Self-Injury and Suicidal Risk

本研究應用Clark與Watson（1991）的憂鬱與焦慮三元模式（the Tripartite Model of Anxiety and Depression）來說明自傷行為與自殺風險的關連性，本文提出一個自傷與自殺的階層預測模式：首先，負向情感預測焦慮與憂鬱，而（低）正向情感預測憂鬱，接著，焦慮可預測自傷行為，而憂鬱則和自殺危險性關連較強。研究對象為487位大學生，採取自陳式問卷的方式施測，包含自我傷害行為量表、自殺危險程度量表、正負向情感量表、症狀檢核表──90–修正版。以階層迴歸分析與結構方程模式來驗證本研究所提出的自傷與自殺的階層預測模式。研究結果支持假設的自傷與自殺的階層預測模式，另外亦發現，在階層迴歸分析中，焦慮與自傷行為的關連性高於自殺危險性（雖然預測關係都有顯著）。因此本研究主要的發現為「自傷行為與自殺危險性的高相關來自於負向情感與焦慮」，不過「憂鬱與（低）正向情感僅與自殺危險性有關」。所以這個模式有兩條主要路徑：一、負向情感能預測與解釋焦慮和憂鬱，且能透過焦慮預測自傷與自殺，唯焦慮對自傷的解釋力較高；負向情感亦能透過憂鬱預測自殺，但無法透過憂鬱預測自傷。二、（低）正向情感能預測與解釋憂鬱，且能透過憂鬱預測自殺。

Objectives: The current study applies and expands the Tripartite Model of Anxiety and Depression to elaborate the link between non-suicidal self-injury (NSSI) and suicidal behavior. We propose a structural model of NSSI and suicidal risk, in which negative affect (NA) predicts both anxiety and depression, low positive affect (PA) predicts depression only, anxiety is linked to NSSI, and depression is linked to suicidal risk. Method: Four hundreds and eighty seven undergraduates participated. Data were collected by administering selfreport questionnaires including the Positive and Negative Affect Schedule, the Deliberate Self-Harm Inventory, the Scale of Suicidal Risk, and the Symptom Checklist-90-R. We performed hierarchical regression and structural equation modeling to test the proposed structural model. Results: The results largely support the proposed structural model, with one exception: anxiety was strongly associated with NSSI and to a lesser extent with suicidal risk. The conclusions of this study are as follows: The co-occurrence of NSSI and suicidal risk is due to NA and anxiety, and suicidal risk can be differentiated by the presence depression and low PA. That is, in this model, there are two pathways. First, NA predicts anxiety and depression, and predicts NSSI and suicidal risk through the mediation of anxiety. NA also predicts suicidal risk through the mediation of depression. Second, low PA predicts depression and also predicts suicidal risk through the mediation of depression. Further theoretical and practical implications are discussed.