Confounding: A cohort study is conducted to assess the relationship between smoking and esophageal cancer.
|
Cancer
|
No Cancer
|
Total
|
|
Smoker
|
110
|
140
|
250
|
|
Not a smoker
|
30
|
220
|
250
|
|
Total
|
140
|
360
|
500
|
Researchers are concerned that alcohol consumption may be a confounder. Based on the data provided below, calculate the RR using the Cochran-Mantel-Haenszel method.
|
Alcohol
|
Cancer
|
No Cancer
|
Total
|
|
No Alcohol
|
Cancer
|
No Cancer
|
Total
|
|
Smoker
|
100
|
50
|
150
|
|
Smoker
|
45
|
55
|
100
|
|
Not a smoker
|
15
|
185
|
200
|
|
Not a smoker
|
15
|
35
|
50
|
|
Total
|
115
|
235
|
350
|
|
Total
|
60
|
90
|
150
|