Creamer Mark, Bell Richard, Failla Salvina
Australian Centre for Posttraumatic Mental Health, Heidelberg, Victoria, Australia.
Behav Res Ther. 2003 Dec;41(12):1489-96. doi: 10.1016/j.brat.2003.07.010.
This study investigated the psychometric properties of the Impact of Event Scale -- Revised (IES-R) in two samples of male Vietnam veterans: a treatment-seeking sample with a confirmed posttraumatic stress disorder (PTSD) diagnosis (N = 120) and a community sample with varying levels of traumatic stress symptomatolgy (N = 154). The scale showed high internal consistency (alpha = 0.96). Confirmatory factor analysis did not provide support for a three-factor solution corresponding to the three subscales of intrusion, avoidance, and hyperarousal. Exploratory factor analysis suggested that either a single, or a two-factor solution (intrusion/hyperarousal and avoidance), provide the best account of date. However, correlations among the subscales were higher in the community sample than in the treatment sample, suggesting that the IES-R may be sensitive to a more general construct of traumatic stress in those with lower symptom levels. The correlation between the IES-R and the PTSD Checklist was high (0.84) and a cutoff of 1.5 (equivalent to a total score of 33) was found to provide the best diagnostic accuracy.
本研究在两组男性越南退伍军人样本中调查了事件影响量表修订版（IES-R）的心理测量特性：一组是确诊患有创伤后应激障碍（PTSD）的寻求治疗样本（N = 120），另一组是具有不同程度创伤应激症状的社区样本（N = 154）。该量表显示出较高的内部一致性（α = 0.96）。验证性因素分析未支持与侵入、回避和过度警觉这三个分量表相对应的三因素模型。探索性因素分析表明，单因素或双因素模型（侵入/过度警觉和回避）能最好地解释数据。然而，社区样本中各分量表之间的相关性高于治疗样本，这表明IES-R可能对症状水平较低者的更一般创伤应激结构更敏感。IES-R与PTSD检查表之间的相关性较高（0.84），发现截断值为1.5（相当于总分33）时诊断准确性最佳。
