When does precision matter? Personalized medicine from the perspective of public health
James Wilson
Abstract
Abstract This chapter examines the nature and value of precision in medicine, and in particular how precision medicine has been interpreted as favouring an ‘P4’ approach—one that is predictive, preventative, personalized, and participatory. It is argued that precision is a more controversial goal in medicine than is often acknowledged. A focus on precision will not always be easy to reconcile with other well-established health system goals, such as maximizing health benefit, improving health equity, or even avoiding iatrogenic harm. Given that precision approaches will often compete for resources with less targeted approaches, it is useful to ask how the model of predictive modelling and early intervention (secondary prevention) competes against rather less targeted interventions to improve the social determinants of health (primary prevention). The chapter argues that primary prevention is in general to be preferred to secondary prevention—both on grounds of equity and of cost-effectiveness—and to the extent that health systems end up cutting back on primary prevention to pursue precision medicine, they do their citizens a disservice.