The Strange Case of Beriberi

In 1887 a strange nerve disease, called beriberi,attacked the people in the Dutch East Indies. Symptoms of the disease included weakness and loss of appetite; victims often died of heart failure. Scientists thought the disease might be caused by bacteria. They injected chickens with bacteria from the blood of patients with beriberi. The injected chickens became sick. However, a group of chickens that were not injected with bacteria also became sick.

One of the scientists, Dr. Eijkman, noticed something. Before the experiment, all the chickens had eaten whole-grain rice, but during the experiment, the chickens were fed polished rice, which matched the diet of the people in the Dutch East Indies. Dr. Eijkman researched this interesting case and found that polished rice lacked thiamine, a vitamin necessary for good health.

• How do I crest a hypothesis for this case study?
• How would I define the independant and dependenct variable?