Nudge: Concept,Effectiveness, and Ethics

Nudges are psychologically informed tools designed to promote behavioral change in order to improve health and well-being. In this review, we focus on three areas of concern: theory, evidence base, ethics. We begin by discussing the problems arising from the theoretical framework that nudges are based on and propose an alternative framework that helps to classify nudges into two types (Type 1 and Type 2). We then evaluate the evidence for nudges in the health domain, drawing attention to critical empirical issues (internal and external reliability) that explain the limited evidence base for their effectiveness. The review ends with an examination of the implications of the theoretical and empirical issues we discussed with respect to current debates regarding the ethics of nudge.