Question

Do placebos really work? Researchers in Japan conducted an experiment on $13$1 individuals who were extremely allergic to poison ivy. On one arm, each subject was rubbed with a poison ivy leaf and told the leaf was harmless. On the other arm, each subject was rubbed with a harmless leaf and told it was poison ivy. All the subjects developed a rash on the arm where the harmless leaf was rubbed. Of the

$13$subjects, 11 did not have any reaction to the real poison ivy leaf.

(a) What was the placebo in this experiment?

(b) Explain how the results of this study support the idea of a placebo effect.

Short answer

(a) The placebo is harmless leaf.

(b) Rash developed due to under active treatment on placebo arm.

Step-by-step solution

Given Information

Research is done on $13$individuals who are prone to allergy. Harmless leaf is applied to experience results one arm. Poisoned leaf on the other arm. All developed rash where leaf was rubbed. Out of them, $11$did not have any reaction,

To determine placebo.

Placebo refers to inactive substance accessed the potency of medication. Hence, harmless leaf was placebo.

To explain how placebo affect results.

This is due to the fact rash is developed on arm where harmless leaf was applied (placebo). They also thought they were under active treatment (toxic leaf). It promotes placebo effect.