Nadine conducted a pretest-posttest control group design. The comparison group received traditional lecture of course content while the treatment group received the lecture and instructor-provided summary notes. She found, however, no differences between conditions, due in part to students sharing the instructor summaries across conditions. This is an example of
A) compensatory rivalry.
B) treatment diffusion.
C) placebo effect.
D) experimenter effects.

Question

Quizplus · Accepted Answer

The phenomenon described is known as treatment diffusion, where the treatment intended for the treatment group leaks into the control group, making it difficult to detect differences between the groups. Compensatory rivalry refers to the control group increasing their effort to "compete" with the treatment group, placebo effect refers to the psychological impact of receiving a treatment (even if it's a placebo), and experimenter effects refer to the unintentional bias introduced by the experimenter. None of these fully explain the situation described.

Nadine Conducted a Pretest-Posttest Control Group Design