Question

Some grocery stores offer their customers sanitizing wipes to wipe down the handles of their shopping cart in hopes of limiting the spread of germs by shopping cart handles. You decide to conduct a study to see if there is an association between wiping down a shopping cart handle and catching a cold. You enroll 200 people that have a cold or the flu from doctor’s offices at St. Jude’s medical center. You enroll 200 people who do not have a cold or the flu (controls) from CSUF. In your questionnaire, you ask each respondent if they’ve used a sanitizing wipe to wipe down their shopping cart at least once in the past two weeks. It turns out that 85 people who had a cold/flu used a sanitizing wipe for their grocery cart; 127 controls used a sanitizing wipe.

	Y	Z
W	A	B
X	C	D

Consider the exposed to be people who used sanitizing wipes. For the 2 x 2 table above, the correct labels for the columns are:

Answer 1

The subjects who are exposed with the disease are 200 and those who are healthy (control) is also 200. Among them 85 who are diagnosed with flu used sanitary wipes and among healthy 127 had used sanitary wipes. So these can be considered as A and B respectively as per the Odds ratio.

C and D are the rest of the subjects without flu who did not use sanitary wipes and control who did not have flu and didint use sanitary wipes.