Logical, consistent use of the best available evidence from proven basic scientific sources, preferably augmented as necessary by facts from current verified peer-reviewed research, to inform policy decisions and routine practice. This approach to decision making ought to apply to all aspects of life, for instance, decisions in courts of law, as well as in biomedical science, medical practice, and public health. The evidence used in decision making should be systematically collected, assessed, and applied, bearing in mind the hierarchy of evidence when considering its quality, validity, and relevance. In considering evidence, the standards of proof vary and are often passionately debated. Direct observation and precise measurement are regarded as solid evidence that can provide firm proof in many circumstances. On the other hand, epidemiological evidence is mainly circumstantial, thus giving opponents of public health measures based on epidemiological evidence many opportunities to refute it. Lawyers representing the tobacco industry, for instance, have often been successful in refuting epidemiological evidence, although in recent years they have found it increasingly difficult to deny the weight of accumulated evidence that tobacco is harmful. See also Hill's criteria and logic.
Subjects: Public Health and Epidemiology.