vidence - Based Public Health Policy and Practice : romises and Limits

athering scientific information for decision making in the United States dates back to the mid-1800s when, in 1863, President Abraham incoln established the National Academy of Sciences o get advice on technical matters from the leading hinkers in the United States.1 The use of scientific nowledge for policymaking has since grown in imporance, fueled by the growth in information, increasing eliance on technologies, and the need to balance enefits and harms in decision processes. The complexity and potential utility of information ow available for guiding policy and practice decisions ave led to methods for synthesis of research informaion.2,3 To assimilate large bodies of research informaion, systematic reviews are undertaken that apply strategies that limit bias in the systematic assembly, ritical appraisal, and synthesis of all relevant studies on specific topic.”4 For clinical practice decisions, the ochrane Collaboration and the U.S. Preventive Serices Task Force are among several groups that have ystematized evidence-based approaches.5,6 These efforts ave been designed to distinguish effective interventions rom those that are less likely to work and to highlight oids in knowledge about effective interventions. What began in the 1980s as the Oxford Database of erinatal Trials evolved into a library of over 2170 ystematic reviews. The Cochrane database of reviews of linical interventions exceeds any in public health.5