23 January 2018 - Publication of interim results of randomised trials can be consequential, potentially undermining trial integrity by unblinding or encouraging dropouts and cross-overs, introducing uncertainty because results based on fewer outcomes are less precise, or overstating true treatment effects as demonstrated primarily in trials terminated early but also in ongoing trials.

Nevertheless, because interim results are new and often promising, they may generate substantial interest, which can be misleading if results change. 

Woloshin et al. describe the characteristics of interim publications from ongoing randomised trials and compare their consistency and prominence with those of final publications.

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