How does COVID stress vary across the anxiety-related disorders? Assessing factorial invariance and changes in COVID Stress Scale scores during the pandemic

BACKGROUND: No studies have examined whether levels of COVID stress vary across anxiety-related disorders. Likewise, no studies have assessed structural invariance of the COVID Stress Scales (CSS) across clinical diagnoses. We sought to address these issues in the present study. Given the dynamic nature of pandemics, we also assessed whether COVID stress changed from the first to third wave in those with clinical diagnoses and those with no mental health conditions. METHOD: Data were collected during COVID-19 from two independent samples of adults assessed about a year apart (early-mid in 2020, N = 6854; and early-mid 2021, N = 5812) recruited from Canada and the United States through an online survey. Participants provided demographic information, indicated the presence of current (i.e., past-year) anxiety-related or mood disorder, and completed the CSS. RESULTS: The five CSS were reliable (internally consistent), and the five-factor structure was stable across samples. Scores tended to be highest in people with anxiety-related or mood disorders, particularly panic disorder. As expected, scores fluctuated over time, being higher during the early phases of the pandemic when threat was greatest and lower during the later phases, when vaccines were deployed and the COVID-19 threat was reduced. CONCLUSION: The findings add to the growing number of studies supporting the psychometric properties of the CSS. The results encourage further investigations into the utility of the scales, such as their ability to detect treatment-related changes in COVID-19-related distress. The scales also show promise for studies of future pandemics or outbreaks because the CSS can be modified, with minor wording changes, to assess distress associated with all kinds of disease outbreaks.