Information Retrieval for Evidence-based Practice Fall 2001 Suzanne Bakken, RN, DNSc, FAAN School of Nursing & Department of Medical Informatics Columbia University

Definition Information retrieval (IR) is the science and practice of identification and efficient use of recorded media

Information Retrieval and Analysis Indexing (using standardized terminology and other methods) Query formulation Retrieval Evaluation and refinement

Relevance Recall - ratio of number of documents retrieved and relevant to number of relevant documents in database (sensitivity) Precision - ratio of relevant documents retrieved to total number of documents retrieved (positive predictive value)

User-defined Relevance Information content of document Provision of references to other sources of information Subjective qualities Situational aspects - clinical vs. student

Types of Clinical Decisions Diagnostic reasoning - differential diagnosis Decisions related to actions - involve risk: cost, time, morbidity, mortality, discomfort Diagnostic tests - treatment-threshold Screening Management (including prevention) - medications, surgery, education, watchful waiting

General Search Strategy for EBP Information Retrieval Clinical problem Define searchable question Select most likely resource Design search strategy Summarize the evidence yield Poor Apply the evidence Select another resource

General Search Strategy for EBP Information Retrieval Clinical problem Define searchable question Select most likely resource Design search strategy Summarize the evidence yield Poor Apply the evidence Select another resource

Elements of Well-built Clinical Questions Patient or problem being addressed “Intervention” (natural or therapeutic) being considered Comparison intervention being considered, where relevant Outcome of interest