Designing Biochemical Visual Literacy Assessments: Insights from Classroom Testing and Student Interviews

A critical skill that biochemistry students must develop is the interpretation of molecular images, ranging from macromolecular representations to the chemical structures of the building blocks that comprise them. Such analysis requires biomolecular visual literacy, which is not often explicitly taught, and can be challenging for instructors to assess. In this work, we examine student responses to assessments designed to probe biomolecular visual literacy. Analysis of sets of assessments with classical test theory indicates that items which have undergone an iterative validation process, including expert review, perform well in classroom testing. However, the evaluation of multiple-choice and multiple-select assessment items based on classroom testing alone has limitations. Therefore, semistructured student interviews were used to explore student approaches to molecular visualization problem solving. Qualitative analysis of interview transcripts identified several common strategies among students when solving image-based questions, including relying on color in the images to answer questions, drawing on familiar terminology in the prompt, and using process-of-elimination to identify the best answer. Image complexity was identified as a common challenge for students. Instructors can craft more effective assessments by paying careful attention to the use of color in images, using terminology students are familiar with, carefully creating distractors, and using images with complexity appropriate to the learner level. This work underscores the importance of the student perspective in the design of assessments used by educators to evaluate learning.