Journal of Anesthesia

, Volume 26, Issue 5, pp 802–803 | Cite as

Internal validity and the risk of bias: a case for a comprehensive review

Letter to the Editor


Allocation Concealment Biases Masking Randomized Trials 


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Copyright information

© Japanese Society of Anesthesiologists (outside the USA) 2012

Authors and Affiliations

  1. 1.Biometry Research Group, National Cancer Institute, and UMBCBethesdaUSA

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