<p>Populism has become a defining feature of European democracies, prompting extensive scholarly debate about its impact on political processes. This study refines the measurement of populist attitudes in Europe by using data from Round 10 of the European Social Survey. Through Confirmatory Factor Analysis, Measurement Invariance testing, and Regression Modelling, the study develops and validates scales grounded in the core dimensions of populism: Anti-Elitism and People-Centrism. The findings confirm the conceptual distinction between these subdimensions and establish the cross-national validity and comparability of the proposed measures. The analysis further explores the associations between populist attitudes, socio-demographic characteristics, and political behaviour, thereby establishing the criterion validity of the scales. The validated measures provide a valuable tool for studying populism at the individual level and for analysing its broader implications for democratic politics across diverse contexts. By offering a robust, theory-driven, and replicable methodological framework, this research enhances the reliability of comparative studies and contributes to ongoing efforts to address the replication crisis in the social sciences.</p>