Safety in numbers 2: Competency modelling and diagnostic error assessment in medication dosage calculation problem-solving

Accurately defining and modelling competence in medication dosage calculation problem-solving (MDC-PS) is a fundamental pre-requisite to measuring competence, diagnosing errors and determining the necessary design and content of professional education programmes. In this paper we advance an MDC-PS competence model that illustrates the relationship between conceptual competence (dosage problem-understanding), calculation competence (dosage-computation) and technical measurement competence (dosage-measurement). To facilitate bridging of the theory–practice gap it is critical that such models are operationalised within a wider education framework that supports the learning, assessment and synthesis of cognitive competence (the knowing that and knowing why of MDC-PS) and functional competence (the know-how and skills associated with the professional practice of MDC-PS in clinical settings).Within the context of supporting the learning and diagnostic assessment of MDC-PS we explore PhD fieldwork that challenges the value of pedagogical approaches that focus solely on abstract information, that isolate the process of knowledge construction from its application in practice settings and contribute to the generation of conceptual errors. We consider misconceptions theory and the concept of mathematical ‘dropped stitches’ and offer an assessment model and program designed to diagnose flawed arithmetical operation and computation constructs.