Medical researchers often use placebos during clinical trials — while one group receives the drug being tested, a control group receives the placebo (often a sugar pill with no medicinal value). All of the test subjects know upfront that they may receive the drug or they may receive the placebo. After the trial, the results of the two groups are evaluated and if the group that got the real drug shows signs of improvement that exceed the group with the placebo, the drug is assumed to be successful.
The placebo effect occurs when a patient's symptoms are alleviated by using the placebo or a proven ineffective treatment. Apparently, this happens because the individual believes or expects that the pill or treatment is going to make them better; therefore, it does. It's a case of mind over matter, and some researchers consider this to be an important aspect of the human body and the link between positive thinking and healing. Other doctors dismiss the placebo effect as a fault in the testing system.
What does Cliff think? Having a positive outlook about overcoming your obstacles certainly can't do harm. When you go to the dentist thinking, "This is going to hurt," guess what? It usually hurts. The opposite is true, too. So if you find yourself with too-frequent negative thoughts, here's a reason to work on changing that.