This real patient illustrates real challenges of general practice: incomplete information, evolution of illness, clinical uncertainty, and providing good care in an imperfect system.1

Mrs Prior caught the attention of her general practitioner during her husband's scheduled consultation. Caring for the “secondary patient” is part of general practice, occurring in up to 18% of encounters.2 This initial evaluation was necessarily brief, yet dealt with three problems: itch, rash, and cystitis.

Blood tests are sometimes used as a temporising tactic, but …