Kinds of patients

The basic goal of health outcomes research is to identify the kinds of patients who do (or do not) benefit substantially from specified medical or surgical treatments and procedures. Similarly, clinicians must determine whether particular patients are the kinds of patients who do (or do not) benefit from specified interventions. Such a kinds-based approach to clinical practice is often resisted, however, when physicians are asked to standardize their practices based on the results of health outcome data. In such settings, clinicians often assert that "every patient is unique". The present paper explores the coherence of this claim. In particular, I examine the applicability of the philosophical notion of natural kinds to a kinds-based approach to clinical research and practice. I conclude that the claim of patient uniqueness is misguided. Two key difficulties with a kinds-based approach are examined: the problems associated with (1) assigning single-case probabilities and (2) stereotyping and discrimination.