Revisiting the Assessment of Critical Thinking and Its Relationship with University Students’ Learning Achievement in Thai University Students

Critical Thinking (CT) plays a crucial role in twenty-first-century education in Thailand, particularly at the university level. This study aims to revisit CT in university students and explore its relationship with learning achievement. The seven aspects of the 35-item Critical Thinking Self-Assessment Questionnaire were modified. The four new aspects of CT were developed through EFA (Exploratory Factor Analysis) and Rasch analysis to assess the validity and reliability of the instrument. These newly developed aspects include Inquisitive Fact-Seeking (IFS), Critical Confidence in Analysis (CCA), Systematic Thinking (ST), and Open-Mindedness (OM). The findings indicate that Thai university students demonstrate an overall CT skill level of 71%. The highest aspect is OM (76.4%), followed by IFS (74.2%), while CCA and ST are considerably lower (67.4% and 66%, respectively). Low CT skills may primarily result from a heavy reliance on rote memorization, a cultural norm of deferring to authority, and long-standing passive learning practices. Furthermore, correlation analysis revealed a modest but significant positive relationship between Critical Thinking Self-Assessment Scale (CTSAS) and Grade Point Average (GPA; r = 0.216, p < 0.01), suggesting that higher CT skills are linked to better learning achievement. Multiple regression analysis indicated that the model explained 5.6% of the variance in GPA (R² = 0.056), with IFS as the only significant predictor (β= 0.223, p = 0.012), suggesting that greater IFS is associated with higher academic achievement. CT may boost academic achievement by strengthening key skills, promoting interdisciplinary thinking, and enhancing student engagement.