(b) This study is not an experiment because the treatments were not actively imposed by the examiners. 25 hospitals do not amount to enough subjects. the women were not matched into pairs. there is only one response variable. (c) Select the best explanation on why confounding will prevent this study from discovering which treatment is more effective. The women were not matched into pairs. The treatments were not actively imposed by the examiners. The study needs to be double-blind in order to accurately discover which treatment is more effective. You cannot distinguish the effect of the treatment from the effects of lurking variables, such as those with cancer at different stages and different opinions of different doctors. Question Source