Assessing student understanding in the molecular life sciences using a concept inventory

Concept inventories are rigorously validated web-based multiple choice instruments that are designed to evaluate the nature and quality of student understandings of key concepts. Such tests can also reveal any related alternative conceptions and visualization difficulties, thereby providing educators with vital feedback about their students’ learning and, in turn, their own teaching practice and pedagogical content knowledge. Students receive rapid diagnostic feedback on their understanding of key concepts and remediation can be targeted by the educator towards problematic areas. This paper describes the process that is being used to develop and validate a concept inventory, which is tailored for use by instructors teaching introductory university courses in biochemistry and molecular biology. The initial phase of the project has involved the identification of the concept domain through a set of “Big Ideas” which are unique to the molecular life sciences and which capture, in a comprehensive and future-looking way, thinking by experts in the field. In the second phase of the project, a draft set of key concepts that underpin understanding of these “Big Ideas”, and which are at an appropriate level of discreteness and specificity to be tested through the concept inventory, has been identified. These include equilibrium, protein structure, metabolic energy and coding of information. A refined set of adaptive questions has been developed around the key concept of chemical equilibrium. Statistical tools to analyse questions for reliability and validity have been trialled and a series of interviews has been conducted to examine students’ alternative conceptions. A second set of questions on protein structure has been developed and is currently being refined as an adaptive test.