For Questions , Use the Following Narrative

For Questions , use the following narrative
Narrative: Aspirin and polyps
A well-designed experiment by the Ohio State University Medical Center studied whether or not taking an aspirin a day would affect colon cancer patients' chances of getting subsequent colon polyps.In the study, 635 patients with colon cancer participated; 317 of them were randomly assigned to the aspirin group, and the other 318 patients were assigned to a placebo (non-aspirin) group.The results showed that 17% of the patients in the aspirin group developed subsequent polyps, compared to 27% of the patients in the non-aspirin group.The results are summarized in the table below.

-{Aspirin and polyps narrative} Compute the test statistic for the data.