In one paragraph of their article in CMAJ's series on new advances in the management of acute coronary syndromes, David Fitchett and colleagues may have substantially oversold the benefit while underestimating the risk of intervention with clopidogrel.1 Benefits were expressed as relative risk reductions of 24% and 20% in the rate of adverse outcomes, although “these benefits were achieved with a small (1%) increase in the rate of bleeding.” Unfortunately, these data were from an as-yet-unpublished study. I suspect that the 1% increase in risk was an absolute risk increase. If the baseline rate of major bleeding was 1%, an absolute risk increase of 1% would be a relative risk increase of 100%, which looks even more scary than a relative risk reduction of 20% or 24% looks good. If the proposed intervention is a good one, its benefits do not need to be inflated by expressing benefits in terms of relative risk and harms in terms of absolute risk.
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