Several studies have reported the factor structure of posttraumatic stress disorder (PTSD) using confirmatory factor analysis (CFA). The results show models with different number of factors, high correlations between factors, and symptoms that belong to different factors in different models without affecting the fit index. These elements could suppose the existence of considerable item cross-loading, the overlap of different factors or even the presence of a general factor that explains the items common source of variance. The aim is to provide new evidence regarding the factor structure of PTSD using CFA and exploratory structural equation modeling (ESEM). In a sample of 1,372 undergraduate students, we tested six different models using CFA and two models using ESEM and ESEM bifactor analysis. Trauma event and past-month PTSD symptoms were assessed with Life Events Checklist for DSM-5 (LEC–5) and PTSD Checklist for DSM-5 (PCL–5). All six tested CFA models showed good fit indexes (RMSEA = .051–.056, CFI = .969–.977, TLI = .965–.970), with high correlations between factors (M = .77, SD = .09 to M = .80, SD = .09). The ESEM models showed good fit indexes (RMSEA = .027–.036, CFI = .991–.996, TLI = .985–.992). These models confirmed the presence of cross-loadings on several items as well as loads on a general factor that explained 76.3% of the common variance. The results showed that most of the items do not meet the assumption of dimensional exclusivity, showing the need to expand the analysis strategies to study the symptomatic organization of PTSD.

中文翻译：

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使用探索性结构方程模型 (ESEM) 检查创伤后应激障碍症状的内部结构

一些研究使用验证性因子分析 (CFA) 报告了创伤后应激障碍 (PTSD) 的因子结构。结果表明，不同模型的因子个数不同，因子之间的相关性高，症状在不同模型中属于不同因子，不影响拟合指数。这些元素可以假设存在相当大的项目交叉加载、不同因素的重叠，甚至存在解释项目共同方差来源的一般因素。目的是使用 CFA 和探索性结构方程模型 (ESEM) 提供有关 PTSD 因子结构的新证据。在 1,372 名本科生的样本中，我们使用 CFA 测试了六种不同的模型，使用 ESEM 和 ESEM 双因子分析测试了两种模型。使用 DSM-5 (LEC-5) 的生活事件清单和 DSM-5 (PCL-5) 的 PTSD 清单评估创伤事件和过去一个月的 PTSD 症状。所有六个测试的 CFA 模型都显示出良好的拟合指数（RMSEA = .051–.056，CFI = .969–.977，TLI = .965–.970），因子之间具有高度相关性（米= .77,标清= .09 至米= .80,标清= .09)。ESEM 模型显示出良好的拟合指数（RMSEA = .027–.036，CFI = .991–.996，TLI = .985–.992）。这些模型证实了几个项目上存在交叉加载，以及解释了 76.3% 的共同方差的一般因素上的加载。结果表明，大多数项目不满足维度排他性假设，表明需要扩展分析策略来研究 PTSD 的症状组织。