400 patients suffering from chronic back pain were randomly assigned to one of two groups. Over a four-month period, the first group received acupuncture treatments and the second group received A placebo. Patients who received acupuncture treatments improved more than those who received The placebo.

Question

Quizplus · Accepted Answer

This is a designed experiment because the researchers actively assigned patients to two different groups (acupuncture vs. placebo) and then observed the outcomes, rather than just observing outcomes in a naturally occurring group setup.

400 Patients Suffering from Chronic Back Pain Were Randomly Assigned