Purpose: To determine whether critical thinking in problem-based learning (PBL) group discourse differed according to case modality.
Method: The study was conducted in 2000 in the Department of Pediatrics at the University of Colorado School of Medicine in Denver. Third-year medical students on their pediatrics clerkship were divided into three groups: face-to-face with a text case, face-to-face with a digital video case, and virtual with a digital video case. Twenty-four groups were divided among the three case modalities. Using an existing coding scheme, each distinct codable unit of discourse was placed into one of 35 indicators reflective of five critical-thinking stages. For each group's discourse, a critical-thinking ratio was calculated for each of the stages. The Kruskal-Wallis test was used to compare the critical-thinking ratios for each stage across the three modalities. Residual conversation to indicate processes occurring within the group was also coded.
Results: A content analysis of the transcripts of 13 of the 24 group discussions occurred. The virtual groups had the highest critical-thinking ratio. Except for the problem-identification stage, the video groups had higher ratios that the text groups did.
Conclusions: This exploratory study examined how the mode of case presentation affected the critical thinking of groups using the PBL format. Students who learned in a virtual modality with a digital video case engaged in more critical thinking. The data suggest that the video enhanced critical thinking in both face-to-face and virtual PBL groups.