For example, when someone develops a mild transient cough, tuberculosis is a “Zebra”. For another example, following the discovery of West Nile fever in New York City in September, 1999, the Centers for Disease Control and Prevention warned doctors to expect more infectious disease “zebras” (disease due to rare microbes).
When diagnosing patients who present with varying symptoms, we need doctors to remember that when they hear hoof beats it could also be a ZEBRA… therefore, “when you hear hoofbeats, consider the ZEBRA!”
Dr. Eugene Woltering of New Orleans is credited with the idea that Carcinoid patients embrace the zebra in order to promote awareness.
This horses vs. zebras principle is known as Occam’s Razor.
Wikipedia tells us that “Occam’s Razor (also spelled Ockham’s Razor) is a principle attributed to the 14th –century English logician and Franciscan friar, William of Ockham. It forms the basis of methodological reductionism, also called the principle of parsimony or law of economy.
It is simplest form, Occam’s Razor states that one should make no more assumptions than needed. Put into everyday language, means: “The simplest explanation is the best.”