Inclusive education is a right and must be offered to all students, including those with disabilities, providing them with individualized educational attention and support. Teachers play a leading role in the inclusive education process, their preparation and attitudes being essential for this process. This study aimed to present the factor structure and reliability of a questionnaire for the assessment of teachers' perceptions about their preparation to support inclusive education. The sample consisted of 605 Spanish primary school teachers who responded to the Evaluation of Teachers' Inclusion Readiness (CEFI-R) Questionnaire. Exploratory and confirmatory factor analysis and reliability evaluation were performed. The results showed a factor structure with four dimensions (Conception of Diversity, Methodology, Supports and Community Participation), composed of 17 items, with good and excellent goodness-of-fit values and high reliability (Cronbach's Alpha = 0.75-0.94). Thus, the CEFI-R can be considered a quick and easy-to-apply tool to analyze primary school teachers' perceptions about their preparation to address their students' diversity of needs, allowing stakeholders to take actions to promote inclusive education.
Keywords: diversity; inclusive education; perceptions; preparation; primary schools; teachers.