Abstract
Objective
To illustrate controversial issues associated with stopping randomized controlled
trials (RCTs) early for apparent benefit.
Study Design and Setting
The article presents our review of prior relevant work and our research group's reflections
on early stopping.
Results
Compelling evidence suggests that trials stopped early for benefit systematically
overestimate treatment effects, sometimes by a large amount. Unresolved controversies
in trials stopped early for benefit include ethical and statistical problems in the
interpretation of results.
Conclusions
The best strategy to minimize the problems associated with early stopping of RCTs
for benefit is not to stop early. As an alternative, we suggest a threefold approach:
a low P-value as the threshold for stopping at the time of interim analyses, not to look
before a sufficiently large number of events has accrued and continuation of enrollment
and follow-up for a further period.
Keywords
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Article info
Publication history
Accepted:
July 22,
2007
Identification
Copyright
© 2008 Elsevier Inc. Published by Elsevier Inc. All rights reserved.
