Psychometric properties, Rasch analysis, and measurement invariance of the Turkish Brief Self-Control Scale in early adolescents: exploring the mediating role of responsibility in the self-control and patience association.

Introduction: This study aimed to rigorously evaluate the psychometric properties of the Brief Self-Control Scale (BSCS) for use with early adolescents aged 10-14 years within Turkish culture. Given developmental differences in cognitive and self-regulatory capacities during early adolescence, the study sought to determine whether the original scale structure is appropriate for this age group and cultural context, and to optimize the instrument for preliminary screening purposes. Methods: Data were collected from 351 secondary school students (mean age = 11.73; 50.4% girls). A dual analytical framework integrating ordinal confirmatory factor analysis (CFA) and Item Response Theory was employed. Rasch analysis using the Partial Credit Model was conducted to examine item-level functioning, threshold ordering, and developmental appropriateness. Items demonstrating poor psychometric performance or cognitive mismatch were diagnostically removed. Following item refinement, multigroup CFA was performed to test measurement invariance across gender at the configural, metric, scalar, strict, and structural levels. Concurrent and nomological validity were examined using the Responsibility and Patience Scales as external criteria. Predictive validity was further assessed through a latent mediation model within a structural equation modeling framework. Results: Rasch analysis identified four underperforming items, partly due to disordered threshold parameters indicating developmental incongruence for early adolescents, leading to their removal. The resulting 9-item scale demonstrated satisfactory model fit. Multigroup CFA confirmed full measurement invariance across gender. The refined BSCS-9 showed meaningful positive associations with responsibility and patience, supporting concurrent and nomological validity. In the latent mediation model, responsibility emerged as a significant mediator between self-control and related character traits, providing robust evidence for the predictive validity of the scale. Discussion: The findings establish the Turkish BSCS-9 as a parsimonious, developmentally appropriate, and psychometrically robust preliminary screening tool for assessing low-to-moderate levels of self-control in early adolescents. The integration of ordinal CFA with Rasch modeling offered a nuanced and methodologically consistent evaluation, highlighting the importance of aligning measurement instruments with developmental stage characteristics. Overall, this study supports the utility of the Turkish BSCS-9 in developmental and educational research contexts and demonstrates the value of combining modern psychometric approaches in scale adaptation and validation studies.