Evidence‐based medicine and limits to the literature search

Summary Rationale, aims and objectives  Searching the literature, a core requirement of evidence‐based medicine has been impossibly oversold. The literature search is supposed to provide evidence independent from expert opinion, which has been deemed to be low on the evidence hierarchy. Yet freedom from expertise is not free. Paradoxically, practitioners are told to search the literature to avoid authority, but because there is too much information and too little time, they are urged to rely on authoritative digests. But the chain of errors inherent in searching literature for decision making, whether in scoping the decision, finding relevant documents, or in the document content, cannot be ignored. This article explores those errors. Method  With examples from signal theory and decision theory, the literature search is analyzed in light of fundamental limits in the nature of informaiton. You can run from expertise but you cannot hide. Expertise is inevitably required to deal with these errors. So do‐it‐yourself searching is inadequate in the absence of expertise. The best decisions result from collaboration with subject matter experts and decision‐making experts.