Development and psychometric evaluation of the attitudes toward inclusive educational practices for students with special needs scale (ATIEP-SN)

Positive teacher attitudes are central to implementing inclusive education and supporting the participation of students with special needs. This study aimed to develop and psychometrically evaluate the Attitudes Toward Inclusive Educational Practices for Students with Special Needs Scale (ATIEP-SN) for pre-service teachers. An exploratory sequential mixed-methods scale development design was employed. Semi-structured interviews were conducted with 21 pre-service teachers. Expert review, content validity analysis, and cognitive interviews retained a 12-item draft form. The quantitative phase included two independent samples for exploratory factor analysis (n = 613) and confirmatory factor analysis (CFA) (n = 263). Principal axis factoring supported a strong one-factor structure, with an eigenvalue of 8.52, explaining 68.3% of the total variance. CFA supported the one-factor model. Internal consistency was high, with Cronbach’s alpha and McDonald’s omega values above .96. Composite reliability was .96, and the average variance extracted was .67, supporting model-based convergent validity. An ordered-categorical CFA supported robustness. Multi-group CFA supported configural, metric, and scalar invariance across gender groups. Ordinal logistic regression DIF analysis indicated that none of the items displayed practically meaningful gender-based DIF. Overall, the findings provide evidence for the content validity, internal structure, reliability, model-based convergent validity, robustness, and gender fairness of the ATIEP-SN.