In a double-blind study examining the effects of a new cola-flavored energy drink on people's physiological arousal, participants in the experimental drink condition demonstrated significantly greater arousal than the control group. However, upon further investigation, a third, placebo group (using flavored Coca-Cola), also showed significantly greater arousal than the control group. Which of the following may have influenced the results of this study?
A) participants' expectations about the effects of an experimental energy drink
B) experimenters' expectations about the effects of the experimental energy drink
C) the drink that was used as a placebo
D) A and B
E) A and C
F) all of the above

Question

Quizplus · Accepted Answer

Participants' expectations about the effects of an experimental energy drink (A) may have influenced the results, as they may have anticipated increased arousal due to the experimental nature of the study. Additionally, the choice of the placebo (C) may have also led to increased arousal, as flavored Coca-Cola is still a stimulant and contains caffeine. The experimenters' expectations about the effects of the experimental energy drink (B) could also be a potential factor, but it is not explicitly stated in the question. Therefore, the best answer is E, as both A and C are likely to have influenced the results of the study.

In a Double-Blind Study Examining the Effects of a New