Question

1. In order to study the relationship between uranium mining and lung cancer in West Virginia, 3,500 people with incident lung cancer were identified through cancer registries. 4,300 people without lung cancer were selected from the DMV registries. Uranium mining data was collected through mailed questionnaires. Uranium mining was reported by 925 of the people with lung cancer and 955 of those without lung cancer respectively, while the others reported no uranium mining.
   1. What study design was employed? Mention in short answers the key characteristics that make this a _____________study. (2 points)
   2. Calculate and interpret the appropriate measure of association for the uranium mining and lung cancer association. Show your work. (2 points)

Answer 1

This is experimental study design.

People were divided among two groups( withl ung cancer & without lung cancer) and then questionnaires results are reported separately for both groups.

We can use 'Two Proportion Z-Test' to interpret uranium mining and lung cancer association.

Null hypothesis: There is no association between uranium mining and lung cancer

n1= 3500

n2= 4300

p1 = 925/3500

p2 = 955/4300

overall sample proportion, p = (925+955)/(3500+4300)

= 0.042/0.0097

= 4.33

We need to find out if the z-score falls into the “rejection region.”

The z-score associated with a 5% alpha level / 2 is 1.96

4.33 > 1.96, so we can reject the null hypothesis.

So, people with Uranium mining are more prone to lung cancer.