Evidence and effectiveness in decisionmaking for quarantine.

When public health decisionmakers turned to quarantine during the recent severe acute respiratory syndrome (SARS) epidemic, difficult questions were raised about the legitimacy and acceptability of restrictive measures to attain public health goals. SARS also brought to light how scientific uncertainty can permeate public health decisionmaking, leading us to think about the relationship between the adequacy of evidence of the effectiveness of an intervention and its role in the justification of public health action. In this article, we critically examine the role of evidence and effectiveness in decision-making for quarantine. It is our contention that the effectiveness of a public health intervention should not be defined exclusively in (absolute and objective) scientific terms but rather conceptualized relationally and normatively in public health decisionmaking.