Open Problem‐Based Instruction Improves Student Outcome on Short Answer Critical Thinking Physiology Questions
Authors: Weaver Chelsea C. , Rivera Patrick R. , Xiang Lin , Taylor Jessica C. , Osborn Jeffrey L. 
Published: April 2020

Classroom instruction has historically focused on teacher‐centered, lecture‐based instruction. However, evidence suggests student‐centered and team‐based approaches stimulate greater knowledge retention, student involvement, and investment in the information. Therefore, we hypothesized that students receiving problem‐based instruction would show greater performance on assessments with regards to total points as well as level of understanding compared to traditional lecture style of instruction. To test this, a quasi‐experimental study was conducted in an upper‐level (junior/senior students) animal physiology course. Students were enrolled in different course sections based on scheduling only and students had no prior knowledge of the instruction style of the course. Three sections were presented with lecture‐based instruction (LI, n=66) and two sections were presented with open problem‐based instruction (OPBI, n=40). The same professor designed and taught all sections and identical course materials were provided to students regardless of instructional group. Students were assessed with 3 exams consisting of 50% multiple choice and 50% short answer questions. Exams were scored blindly. We previously reported that students in OPBI‐based instruction performed better on short answer questions than those in the LI group (LI 47.6 ± 1.1 points vs OPBI 52.0 ± 1.8 points; out of 65 points; p<0.05 t‐test). The present study aimed to assess the short answer responses to determine whether OPBI was associated with higher level responses to critical‐thinking short‐answer questions. This was done through qualitative analysis of questions from exam 1, which covers cellular physiology, membrane potentials, and neuronal function. Responses for these questions were blindly analyzed and scored with a rubric for the following factors: accuracy (0–2 points) based on whether what was written was correct; sufficiency (0–4 points) based on the detail and level of thinking presented in the short‐answer response; and use of technical vocabulary (0–2 points) based on inclusion of physiological terminology. OPBI students scored higher in 2 out of 6 SA questions (Q3 LI 8.9 ± 0.4 points vs OPBI 10.3 ± 0.3 points; Q5: LI 10.1 ± 0.5 vs OPBI 11.8 ± 0.2; out of 12 points each; p<0.05 t‐test). Accuracy (LI 1.5 ± 0.5 vs OPBI 1.8 ± 0.3 points), sufficiency (LI 2.8 ± 1.0 vs OPBI 3.3 ± 0.8 points), and technical vocabulary usage (LI 1.4 ± 0.5 vs OPBI 1.7 ± 0.4 points) were higher for students in OPBI compared to LI for both questions (p<0.05 t‐test). Students in OPBI exhibit greater perceived understanding and technical vocabulary usage, resulting in more sufficient and accurate in‐depth responses to questions that challenge students to think critically. This strongly suggests that an open‐problem, active‐learning based instructional style not only results in retention of information, but a deeper level of understanding. Future studies include comparing additional responses and exam question wording to investigate why OPBI may have better prepared students for some questions but not all.