Project 1 (Probability)- It is almost never lupus!: Lupus is a medical phenomenon where antibodies that are supposed to attack foreign cells to prevent infections instead see plasma
proteins as foreign bodies, leading to a high risk of blood clotting. It is believed that 2% of the population suffer from this disease. The test is 98% accurate if a person actually has the disease.
The test is 74% accurate if a person does not have the disease. There is a line from the Fox
television show House that is often used after a patient tests positive for lupus: “It’s never
lupus.”
Do you think there is truth to this statement? In other words, what is the probability that someone does not have lupus, given that they tested positive for lupus.
Draw a tree diagram and use appropriate probabilities to support your answer.
Also, provide some additional information about lupus such as symptoms and risk factors