Who is blinded in randomized clinical trials? A study of 200 trials and a survey of authors

  title={Who is blinded in randomized clinical trials? A study of 200 trials and a survey of authors},
  author={Mette T. Haahr and Asbj{\o}rn Hr{\~o}bjartsson},
  journal={Clinical Trials},
  pages={360 - 365}
Background Insufficient blinding of persons involved in randomized clinical trials is associated with bias. The appraisal of the risk of bias is difficult without adequate information in trial reports. Purpose We wanted to study how blinding is reported in clinical trials and how lack of reporting relate to lack of blinding. Methods A cohort study of 200 blinded randomized clinical trials published in 2001 randomly sampled from the Cochrane Central Register of Controlled Trials, and a… Expand

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