In a study of 1000 people, investigators observed who was bitten by a flea and w
ID: 3119923 • Letter: I
Question
In a study of 1000 people, investigators observed who was bitten by a flea and who subsequently developed plague. The data are shown in the table below. Compute the risk of developing a plague for those with no flea bite. Compute the relative risk of developing a plague for those with flea bite and those without flea bite. Compute (lie odds of plague for those with flea bite. Compute the odds of plague for those without frost bite. Calculate the odds ratio using the results from parts (c) and (d). Use the formula: Odds ratio = Relative Risk times (1 - P_2/1 - p_1)Explanation / Answer
a.) Risk after flea bite = 400/600 = 67%
b.) Risk with no bite = 100/400 = 25%
c.) Relative risk = 67/25 = 2.68
d.) Odds of plague for those with flea bite = no. case with the plague / no of case with plague = 400/200 = 2
e.) Odds of plague for those without flea bite = no. case with the plague / no of case with plague = 100/300 = 0.33
f.) Odds ration would be = 2/0.33 = 6.06