Abstract: Stressful contexts like the COVID-19 pandemic precipitated remarkable socio-economic changes, exacerbating universal uncertainty and a pervasive loss of control. Improving mental health outcomes on the operational definition and measurement of related concepts. This study analyzed cross-sectional data from 20 countries and regions, collected between January 25 and November 10, 2021. Psychometric evaluation occurred in two stages: initially, item review and factor analysis with a 2,749 adult sample from Mainland of China and Hong Kong SAR; subsequently, confirmation of factor structure, measurement invariance testing, and advanced analyses with a 4,000 adult sample from 20 countries and regions. A six-item, single-factor structure was verified, confirming satisfactory factor loading, fit indices and consistency. Measurement invariance across geographies and groupings was also confirmed. Three Out-of-Control profiles representing low, medium, and high stress levels, were identified, with age, depression/anxiety symptoms, education, socio-economic status, and exposure to COVID-19-affected acquaintances significantly influencing affiliation. The item “I think I cannot control things that I previously could” was the most critical node. This newly validated scale represents a substantial advancement in measuring stress within the context of global health crises, thus enhancing comprehension of psychological responses. Continual evaluation of the scale’s effectiveness and accuracy is crucial.