Depiction of Health 2021; 12(1): 34-43 http://doh.tbzmed.ac.ir Original Article Effect of Problem-Based Learning and Reasoning Tests on Learners' Critical Thinking Skills Before and After the Educational Intervention in Graduate Students of Basic Sciences Vahideh Zarea Gavgani 1 , Hakimeh Hazrati 2 , Zohreh Sohrabi* 2 Abstract Background and Objectives: Critical thinking skills are not learned spontaneously. Higher education system should strengthen critical thinking skills of learners by integrating critical thinking skills into educational programs. The aim of this study was to investigate the effect of problem-based learning and reasoning tests on strengthening learners' critical thinking skills before and after the educational intervention in graduate students of basic sciences. Material and Methods: This study is a quasi-experimental study that was conducted in 2020 at Tabriz University of Medical Sciences and Iran. Participants in the study were graduate students in the fields of medical education and Medical Library and Information Science. Problem-based learning theory and application of reasoning tests in the level of critical thinking of learners before and after the educational intervention; the California Critical Thinking Questionnaire was reviewed. Data analysis was performed using SPSS 19 software. Statistical methods such as frequency, percentage and mean standard deviation have been used to study descriptive statistics and the significance level of the data has been investigated using nonparametric Wilcoxon test. Results: The level of critical thinking of students in the field of medical education before the educational intervention was moderate (2.92 ± 9.01) and weak in the field of Medical Library and Information Science (6.80 ± 80.95). After the educational intervention, the level of critical thinking of learners in both disciplines has significantly increased. In the field of analysis, the rate of critical thinking in both disciplines was lower than other domains before the intervention, which was higher than the other domains after the educational intervention. Conclusion: The present study showed that designing effective educational interventions in the fields of teaching and assessment methods lead to strengthening learners' critical thinking skills. By using new methods of evaluation and teaching, the education system can produce graduate students with the competency to create new ideas and novel approaches. 1. Tabriz Health Services Management Research Center, Health Management and Safety Promotion Research Institute, Department of Medical Library and Information Sciences, Tabriz University of Medical Sciences, Tabriz, Iran 2. Center for Educational Research in Medical Sciences (CERMS), Department of Medical Education, School of Medicine, Iran University of Medical Sciences, Tehran, Iran (Email: Sohrbiz@iums.ac.ir) © 2021 The Author(s). This work is published by Depiction of Health as an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by-nc/4.0/). Non-commercial uses of the work are permitted, provided the original work is properly cited. Citation: Zarea Gavgani V, Hazrati H, Shohrabi Z. Effect of Problem-Based Learning and Reasoning Tests on Learners' Critical Thinking Skills Before and After the Educational Intervention in Graduate Students of Basic Sciences. Depiction of Health. 2021; 12(1): 34-43. Article Info: Article History: Received: 10.18.2020 Accepted: 01.22.2021 Published: 03.21.2021 Keywords: Critical Thinking Assessment Problem Based- Learning Reasoning Tests Graduate Students Basic Sciences DOI: 10.34172/doh.2021.05