Biases in clinical trials with sequential monitoring
نویسندگان
چکیده
Objectives It is well known that a sequentially monitored clinical trial that stops early for benefit has a crude treatment difference that overestimates the true treatment effect. This has led to extended debate in the literature, with some researchers arguing that early stopping is an important source of bias in meta-analyses of clinical trials. We therefore investigated the implications of excluding studies that stopped early, so-called truncated studies, from estimation of treatment effects.
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