A study was conducted to investigate the risk factors for childhood leukemia. The investigators enrolled 100 children with leukemia at the Boston Children's Hospital and compared them to 200 matched neighborhood children without leukemia. The main risk factor was changes in theTP53gene. Among children with leukemia, 8 had a change in theTP53 gene while only 4 children without leukemia had a change in the TP53 gene.

a) Using the information above,

b) Calculate the appropriate measure of association and the 95% CI by hand.

c) Interpret the measure of association and the 95% CI.

d) Is the association statistically significant? What evidence do you have to determine statistical significance?

e) What test would you use to calculate a p-value of the association between changes in the TP53 gene and Leukemia?

	Leukemia	Without leukemia	Total
Change TP53	8	4	12
No change TP53	92	196	288
	100	200	300