In the mid-1990s, a study was conducted to determine if arthroscopic surgery was an effective treatment for arthritis of the knee.Ten men were scheduled for surgery and each patient was anesthetized.But, after each patient was unconscious, the surgeon consulted a randomly generated code to determine whether to do the actual surgery, or to perform a "sham" surgery (make three small incisions in the knee, stitch the patient up, and leave a small scar).This is best described as a(n) _________________ study.
A) voluntary
B) observational
C) medical
D) experimental

Question

Quizplus · Accepted Answer

This study involved the manipulation of a variable (whether the patient received the actual surgery or a sham surgery) to determine its effect on the outcome (arthritis of the knee). This is a classic example of an experimental study.

In the Mid-1990s, a Study Was Conducted to Determine If