Stephen J.LurieMD, PhD, Senior Editor
Copyright 2002 American Medical Association. All Rights Reserved. Applicable FARS/DFARS Restrictions Apply to Government Use.2002American Medical Association
To the Editor: In the WHI trial,1 clinic gynecologists were unblinded to treatment assignment for 41% of women in the estrogen plus progestin group and 7% of women in the placebo group. It is thus uncertain whether the study succeeded in maintaining blinding of other clinical staff to prevent detection bias. Such potential for detection bias is of less concern for more objective clinical outcomes such as stroke, but could be of concern for more uncertain outcomes such as venous thromboembolism. Despite defined algorithms and central training, agreement rates between local and central adjudication were only 84% for MI and 84% for deep venous thrombosis, suggesting that outcome adjudication may not have been independent of treatment assignment.
Garbe E, Suissa S. Risks of Postmenopausal Hormone Replacement. JAMA. 2002;288(22):2822. doi:10.1001/jama.288.22.2822-JLT1211-1-10