Antibiotic or Placebo A large number of surgery patients get infections after surgery, which can sometimes be quite serious.
Researchers randomly assigned some surgery patients to receive a simple antibiotic ointment after surgery, others to receive a placebo, and others to receive just cleansing with soap.
If we wanted to test the association between treatment and whether or not patients get an infection after surgery, would this be a test of homogeneity or of independence? Explain.
(Source: Hospitals could stop infections by tackling bacteria patients bring in, studies find. New York Times, January 6, 2010.)