Development and Validation of COVID-19 Stress Scale (CSS) in an Iranian Non-Clinical Population

Coronavirus disease 2019 (COVID-19) generated profound concerns in public. However, few validated scales measure COVID-related stress. We developed and psychometrically assessed a unique COVID-19 Stress Scale (CSS) in an Iranian non-clinical population. The CSS was developed to evaluate the existing stress measures, specialists' reviews, and interviews with healthy individuals. Experts provided feedback on content validity. The correlation of CSS with the Depression, Anxiety, and Stress Scale 21 (DASS-21) was evaluated to assess convergent validity. Moreover, construct validity and reliability were assessed. Seven items were found acceptable after experts' review. The online method was used to collect information due to the dangerous conditions of COVID-19 and traffic restrictions in Iran. The scale link was shared as an invitation on the virtual social network pages for people to respond. The statistical population of this study included all Iranian people aged 18 - 60. All 755 people, including 511 females and 244 males who completed the questionnaire online, were selected as a sample. Confirmatory Factor Analysis (CFA) showed a one-factor structure. Correlations between items were acceptable, with item-total correlations being 0.49 - 0.58. The CFA resulted in acceptable factor loadings and fit statistics. Internal consistency reliability was found as α = 0.74. Regarding convergent validity, CSS had moderate to strong correlations with the depression (r = 0.53), anxiety (r = 0.59), and stress (r = 0.64) subscales of DASS-21 (P < 0.05). The seven-item CSS demonstrated acceptable psychometric properties and can be a useful measure of research and evaluation. There is a need to test the scale's validity in a random sample and other nationalities.