Educating for Inclusion: PERKIN, the Scale That Measures Future Teachers’ Perceptions

This study aims to develop and validate the scale on the perceptions and knowledge of trainee teachers regarding the inclusion of students with disabilities (PERKIN), designed to assess the perceptions and knowledge of pre-service teachers regarding the inclusion of students with disabilities. Grounded in the recognition of inclusive education as a key pillar for quality and equitable education, this research addresses the need for diagnostic tools to identify strengths and gaps in teacher preparation. The study was conducted in three phases: (a) expert judgement, where the content validity index was calculated; (b) exploratory factor analysis (EFA); and (c) confirmatory factor analysis (CFA). The EFA was conducted with a sample of 342 students from the education faculties of several Spanish universities, while the CFA was conducted with an independent sample of 1,006 future teachers. The final version of the instrument includes 35 items grouped into 4 dimensions: acquired skills, innovative teaching competencies, inclusive organisational awareness, and cultural beliefs about disability. CFA results indicated an acceptable model fit (RMSEA = 0.053; CFI = 0.741; TLI = 0.722), and high internal reliability (total α = .90). In addition, test-retest reliability ( r = .92) and intraclass correlation coefficient (ICC = 0.91) confirmed the temporal stability of the instrument. The PERKIN scale is concluded to be a psychometrically robust and useful tool for assessing the inclusive preparedness of pre-service teachers, offering guidance for training interventions and educational policies aimed at fostering inclusive and quality education.