One of the most significant developments of Romantic medicine was the diagnostic practice of weighing two different kinds of evidence: the patient's narrative and the physical exam. Before the nineteenth century, doctors relied for diagnosis primarily on the patient's report of his or her illness – so much so, that it was not uncommon to treat patients via correspondence. Before the clinical era, physical examination was limited to noting the quality of the pulse (not counting it) and occasionally the examination of bodily fluids. Only in the early nineteenth century did doctors begin to practice thorough palpation, auscultation (listening to body sounds), and measuring various bodily signs (pulse, breathing, temperature). With the rise of clinical medicine, as disease was correlated with local pathology through the post-mortem dissection, doctors began to try to elicit evidence of localized disease in the living patient. Physical signs became as telling as the patient's story, but in a completely different way.

Historians of medicine, especially Nicholas Jewson and Roy Porter, have noted this changing balance of power, from a client-dominated doctor/patient encounter in the early eighteenth century to the rise of medical power in the nineteenth. Building on their research, Mary Fissell tracks the “disappearance of the patient's narrative” in British hospital medicine in the late eighteenth century. Comparing medical case reports with patients' autobiographical accounts, Fissell finds the patient's experience to be increasingly sidelined by clinical reporting. Fissell writes, “The patient's narrative was replaced by physical diagnosis and post-mortem dissection. The body, the disease, became the focus of the medical gaze, not the patient's version of illness.”