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Table 1 Criteria for deciding when to consider a placebo vs. a usual-care control group

From: Should we reconsider the routine use of placebo controls in clinical research?

if the answer to any one of these questions is clearly ‘yes’, use a placebo control; if not, consider the use of a usual-care control condition, even if a credible placebo exists
1 Is the clinical trial being conducted primarily for explanatory reasons?
2 If the trial is being conducted for both explanatory and pragmatic reasons, are the explanatory objectives sufficiently important to sacrifice a potential clinical benefit of a placebo effect?
3 Is the threat of reporting bias so high that there is great danger of obtaining the wrong answer if a placebo is not used?
4 Is the threat of participant withdrawal so great that it is worth sacrificing a potential clinical benefit of a placebo effect?
5 Is there a great threat that the use of concomitant or compensatory therapy may seriously compromise the validity of the trial?
6 Is there a compelling need to study side effects of an intervention and to know if these side effects are specifically related to the study intervention?