Validation and Psychometric Evaluation of the Persian Version of the Düsseldorf Illustrated Schema Questionnaire for Children and Adolescents

Abstract

Objective: This study aimed to validate the Persian version of the Düsseldorf Illustrated Schema Questionnaire and examine its validity and reliability among Iranian children and adolescents.

Methodology: This applied, descriptive cross-sectional psychometric study was conducted among children and adolescents living in Tehran during the 2025–2026 academic year. A total of 310 participants were selected through multistage cluster sampling. The questionnaire underwent forward translation, back-translation, and cultural adaptation. Face and content validity were evaluated by 14 experts using the content validity ratio and content validity index. Confirmatory factor analysis was performed to assess construct validity, while criterion-related validity was examined through correlations between questionnaire dimensions and depression, anxiety, stress, and self-esteem. Internal consistency was assessed using Cronbach’s alpha coefficients.

Findings: The content validity ratios of all items exceeded the acceptable cutoff value of 0.51. Confirmatory factor analysis supported a six-factor structure comprising disconnection and rejection, impaired autonomy and performance, insufficient limits, other-directedness, overvigilance and inhibition, and performance standards. The model demonstrated acceptable fit indices: χ²/df=2.91, RMSEA=0.08, CFI=0.98, NFI=0.96, GFI=0.96, and AGFI=0.94. Standardized factor loadings ranged from 0.34 to 0.81. Schema dimensions were significantly and positively correlated with depression, anxiety, and stress and significantly and negatively correlated with self-esteem. Cronbach’s alpha was 0.88 for the total scale, while subscale coefficients ranged from 0.70 to 0.75.

Conclusion: The Persian version of the Düsseldorf Illustrated Schema Questionnaire demonstrated acceptable preliminary evidence of construct validity, criterion-related validity, and internal consistency. It may therefore be cautiously used in research and preliminary screening of children and adolescents. However, its use for individual clinical diagnosis requires further validation, norm development, determination of cutoff scores, and evaluation in independent clinical and nonclinical samples.