A large international trial recruited 7,000 healthy women and randomly assigned them to receive either tamoxifen or a placebo. The women were followed for a number of years and the breast cancer rates were compared between the two groups. Neither the women nor the treating physicians knew which treatment the women were actually receiving. Which of the following does not apply to this study?

Question

Quizplus · Accepted Answer

This study is described as a randomized experiment because participants were randomly assigned to either the treatment or placebo group. It also mentions a placebo control, indicating that a placebo was used as a comparison to the active treatment, and it was double-blind, meaning neither the participants nor the physicians knew who was receiving the treatment or the placebo. However, it does not fit the description of a case-control study, which involves identifying participants based on the presence or absence of a particular outcome (in this case, breast cancer) and then looking back to see if they were exposed to the risk factor (tamoxifen), which is not the methodology described here.

A Large International Trial Recruited 7,000 Healthy Women and Randomly