Particularism in health care: challenging the authority of the aggregate.

In health care, particularism asserts the primacy of the individual case. Moral particularists, such as Jonsen and Toulmin, reject deduction from universal moral principles and instead seek warrants for action from the multiple sources unique to a given patient. Another kind of health care particularism, here referred to as the knowledge of particulars, is offered as a corrective to evidence-based medicine (EBM), its influence on health care practice and policy, and specifically to EBM's reliance on the aggregate. This paper describes the knowledge of particulars and identifies strategies for its legitimation in health care policy and practice. First, the paper documents the ascendancy of the aggregate through EBM's definition of 'what works' in health care. Second, it delineates the limits of health care knowledge based on the analysis of aggregates, not only for the care of individual patients but for the formulation of policies about patient care. Third, the paper analyses prominent rejections of the particular in contemporary health policy discourse and relates them to larger political purposes. Finally, it depicts the knowledge of particulars as the basis for clinical prudence and offers three potential strategies for promoting particularism as essential to high-quality care.