Yulvinamaesari, Kumaidi, Edi Istiyono
Critical thinking has become an essential 21st-century skill, particularly in physics education, where students must analyse complex phenomena and solve multifaceted problems. However, there is a need for validated instruments to assess high school students' critical thinking skills, specifically within the context of the Indonesian Kurikulum Merdeka. This study aims to (1) test the characteristics of a modified instrument to measure high school students' critical thinking skills in physics and (2) analyse the profile of these abilities. This quantitative survey study was conducted in Makassar city from April to June 2024, involving 11 schools that have implemented the Kurikulum Merdeka. The instrument consisted of 30 multiple choice questions, modified to be relevant to the Kurikulum Merdeka in terms of content and assessment techniques. The trial was conducted with 310 students, and the primary measurement was conducted with 612 Grade XI students. Experts assessed content validity using the Aiken formula, and Confirmatory Factor Analysis (CFA) confirmed the three-aspect structure of the instrument. Item Response Theory (IRT) analysis, employing the one-parameter logistic model, was used to evaluate item characteristics. Content validity assessment showed high validity with a reliability of 0.80. Analysis via IRT revealed that all items had loading factors above 0.5. The measurement results grouped students into five critical thinking categories, with most being at moderate to low levels. These findings indicate the need to strengthen physics learning strategies through more interactive approaches and intensive critical thinking exercises. By understanding students' strengths and weaknesses, teachers can design more effective interventions to improve their critical thinking skills. The validated instrument provides a reliable tool for educators to assess and monitor students' critical thinking development in physics education under the Kurikulum Merdeka framework. © 2025 The Authors, This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
Universitas Negeri Yogyakarta, Indonesia; Universitas Muhammadiyah Kalimantan Timur, Indonesia
