Measuring the Rogerian concept of the fully functioning person in Chinese: Translation and validation of the simplified Chinese version of the Strathclyde Inventory (C-SI-20)

The current study translated and validated the simplified Chinese version of the 20-item Strathclyde Inventory (C-SI-20), a self-report measure of the fully functioning person based on Rogers’ theory. In Sample 1, 450 Chinese-speaking adults completed the C-SI-20 to assess its internal consistency, test–retest reliability, and construct validity. Exploratory factor analysis (EFA) supported a two-factor structure—experiential fluidity and experiential constriction—consistent with findings from the original English version. In Sample 2, data from 226 Chinese-speaking adults were used to conduct confirmatory factor analysis (CFA) and exploratory structural equation modeling (ESEM). Among the models tested, the bifactor ESEM model demonstrated the best fit, indicating that the C-SI-20 captures both a general factor and two specific subdimensions. These findings support the use of the total score as a valid indicator of optimal psychological functioning, while also acknowledging the scale’s multidimensional nature. The C-SI-20 appears to be a reliable and valid instrument for use in Chinese-speaking populations and contributes to the culturally informed study of person-centered theory.