Validating The Core Concept Of "Mass Balance"

We have created a conceptual framework for the core concept of "mass balance." Unlike the previous conceptual frameworks that we have created and validated, the framework for "mass balance" is simply a description in words of the fundamental mass balance equation and the implications of the equation. We surveyed physiology faculty and asked them to rate the importance of "mass balance" as defined by the conceptual framework and also to rate the importance for their students of being able to apply the core concept to liquids, gases, solutes, and solids. Respondents indicated that "mass balance" is important and that our conceptual framework provides a useful tool for teaching and learning. We discuss several examples of how "mass balance" can be used in making sense about a variety of physiological phenomena.