Charon and colleagues [1] correctly draw attention to the rich value of a literary approach to the patient's history. A narrative-based perspective emphasizes the uniqueness of the clinical story and provides a humanistic bridge between the scientific practice and physicians' attempts to address the personal needs and anxieties of their patients. However, Charon and associates omit a further, and potentially equally important, contribution from literary studies; that is, critical theory as applied to the interpretation of clinical research, a discipline that I have called clinical hermeneutics [2].

The "correct" interpretation of clinical research rests largely on understanding the notion of validity. Although much effort—from both epidemiologists and editors—has been invested in the study of internal validity [3], comparatively little progress has been made in defining criteria for external validity (generalizability). The applicability of research data beyond the study population depends on clinical judgment, an inherently slippery art, but an art nonetheless. These murky interpretive waters can be cleared, at least in part, by unravelling the meaning of a research text. This meaning-centered, hermeneutic approach, which aims to apply rules of informal logic and verification to likely conclusions, has a substantial research base in the humanities and offers considerable assistance to readers who wish to judge external validity.

Part of the hermeneutic program is the elucidation of rhetorical devices in the medical and scientific literature. All authors of research texts set out to convey a message to the reader; thus, their conscious or unconscious intention is to persuade. The investigation of the literary elements that make up the persuasive components of a text falls within the ancient and much maligned, but recently reinvigorated, domain of rhetoric. A rhetorical analysis of a scientific text aims to reveal an author's overt and covert narrative intent and to overcome any hidden literary bias [4]. The arguments presented in a scientific paper, their arrangement, and their style of presentation all affect the persuasive force of a text and can be peeled away to expose, and perhaps undermine, the bare interpretive ambitions of the author. This method can also uncover the rhetorical hyperbole that litters the presentation of research data in the media [5]. The rhetorical analysis of a research paper is an underexplored application of literary studies in medicine.