Although the Impact Event Scale–Revised is widely used, its factor structure is still controversial. In addition, its longitudinal measurement invariance (LMI) remains uninvestigated. In this sense, we carried out three studies to investigate its psychometric properties. In Study 1, we evaluated the factorial structure of the scale comparing the different models existing in the literature in Brazilian samples who responded to the instrument during the COVID-19 pandemic. In Study 2, we provide support for a five-factor model throughout convergent validity with psychological distress and sleep problems, and criterion validity between people with diagnostic of mental disorders. Finally, we evaluated the LMI over a 6-month interval. The results indicated that the five-factor model has excellent goodness of fit and holds strict longitudinal invariance. Additionally, internal consistency and stability coefficients indicate that the scale is appropriate to measure posttraumatic stress symptomatology) in nonclinical samples across multiple assessments.

中文翻译：

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事件影响量表的纵向不变性和有效性——在巴西样本中根据 COVID-19 大流行进行修订。


尽管影响事件量表-修订版被广泛使用，但其因素结构仍存在争议。此外，其纵向测量不变性（LMI）仍未得到研究。从这个意义上说，我们进行了三项研究来调查其心理测量特性。在研究 1 中，我们评估了该量表的因子结构，比较了文献中现有的不同模型，其中巴西样本在 COVID-19 大流行期间对仪器有反应。在研究 2 中，我们为五因素模型提供了支持，该模型涵盖了心理困扰和睡眠问题的收敛效度，以及诊断为精神障碍的人之间的标准效度。最后，我们以 6 个月为间隔评估了 LMI。结果表明，五因素模型具有良好的拟合优度，并具有严格的纵向不变性。此外，内部一致性和稳定性系数表明该量表适合测量多次评估的非临床样本中的创伤后应激症状。