Development and Validation of the Korean Stage-2 Culture Index (K-S2CI): A Developmental–Cultural Structural Measure
Abstract
Rapid economic modernization does not always correspond with improvements in psychological well-being. South Korea presents a paradox in which material prosperity coexists with persistently high suicide rates. Existing research has emphasized economic stress, psychiatric disorders, and interpersonal risk factors; however, these variables do not fully account for sustained suicide vulnerability in affluent contexts. The present study introduces and validates the Korean Stage-2 Culture Index (K-S2CI), a multidimensional measure designed to operationalize competitive, shame-based cultural organization at the individual level. Drawing on a developmental–civilizational framework, the K-S2CI integrates five components: competitive identity, shame sensitivity, validation dependency, early emotional separation, and mental health avoidance. A sample of 412 Korean adults completed the 50-item scale along with measures of perfectionism, shame, depression, and suicidal ideation. Confirmatory factor analysis supported a five-factor structure with a higher-order Stage-2 latent factor. Internal consistency was high across subscales (α = .81–.89) and for the second-order factor (α = .93). The K-S2CI demonstrated convergent validity with perfectionism and shame, discriminant validity from depression and neuroticism, and incremental validity in predicting suicidal ideation beyond depressive symptoms and economic stress. These findings support the K-S2CI as a reliable and theoretically coherent measure of competitive shame-based cultural organization. Implications for suicide research and developmental-cultural theory are discussed.