In 1954, Jonas Salk conducted a large-scale controlled experiment involving over 400,000 children to test the effectiveness of a polio vaccine. Each child was randomly assigned to either a control group or an experimental group. Children in the control group were injected with salt water (a placebo); children in the experimental group were injected with the polio vaccine. The experiment was double-blind, meaning that neither the participants nor the researchers knew to which group each child was assigned. Every test subject was followed for six months. Required:
a. What was the point of giving saline solution to the children who didn't get the vaccine? Explain briefly.
b. Would it have been possible to run this experiment in a double-blinded fashion?