Suppose a new postoperative procedure is administered to a number of patients in a large hospital. The researcher can ask the question, Do the doctors feel differently about this procedure from the nurses, or do they feel basically the same way? Note that the question is not whether they prefer the procedure but whether there is a difference of opinion between the two groups.
To answer this question, a researcher selects a sample of nurses and doctors and tabulates
the data in table form, as shown. Use a significance level of 5%.