Thinking horses not zebras frames the problem. Details coming from diagnostic tests give physicians the ammunition to “rule out” what are not the sources of hoof beats.
By leaving no stone unturned, this approach protects against error in. When coupled with the wisdom of considering the common possibilities first, as in the case of focusing on horses not zebras, the diagnostic process can be efficient. But the rapid and multi-faceted introduction of advanced imaging technologies has complicated matters.