Abstract
Background: Due to the limited research examining the psychological impact of coronavirus disease 2019 (COVID-19), our study aims to investigate the effect of the COVID-19 pandemic on psychological outcomes and assess the differences between participants with and without post-traumatic stress disorder (PTSD) on the psychological outcomes as latent factors and items. Methods: An online survey was conducted on 999 participants. The Impact of Event Scale-Revised (IES-R) assessed the psychological impact, while outcomes were measured by Patient Health Questionnaire-9 (PHQ-9), Generalized Anxiety Disorder (GAD-7), and Insomnia Severity Index (ISI). A series of Confirmatory Factor Analysis (CFA), structural equation model (SEM), Multiple Indicators and Multiple Causes (MIMIC), and Differential Item Functioning (DIF) were conducted. Results: The IES-R has significant effects on the psychological outcomes. Participants with PTSD have a higher impact on latent factors (depression, anxiety, and insomnia) than those without PTSD. Among participants, 36.5% experienced moderate to severe symptoms of depression, and 32.6% had mild depressive symptoms. For anxiety, 23.7% of respondents experienced moderate to severe anxiety symptoms, and 33.1% had mild symptoms of anxiety. For the ISI, 51.5% of participants experienced symptoms of insomnia. Conclusion: the IES-R for COVID-19 has a significant impact on depression, anxiety, and insomnia at the level of latent constructs and observed variables.