1. Researchers conducted a randomized controlled trial to examine the relative effectiveness and side effects of morphine and pethidine, drugs frequently used for patient-controlled analgesia (PCA). Patients were 40 women between the ages of 20 and 65 years, undergoing total abdominal hysterectomy. The patients were allocated randomly to receive morphine or pethidine by PCA. At the end of the trial, patients described their satisfaction and pain using a three-point verbal scale (Unhappy/Miserable, Moderately Happy, Happy/Delighted). The results are provided in the table below. Use these data to answer the questions below the table.

a. Construct appropriate plots to explore the relationship between the outcomes (satisfaction, pain) and the two drugs.

b. Conduct a chi-square test to determine if there is a significant relationship between satisfaction level and PCA drug. Assume a 95% confidence level.

c. You are concerned about the reliability of the results you obtained in question b, because some of the expected frequencies are small (

d. Conduct the appropriate statistical test to determine whether the proportion of patients that are happy/delighted with the painlevels for morphine is greater than the proportion happy/delighted with the pain levels for pethidine. Assume a 95% confidence level.

PP ppy, Happy/Delighted). The results are provided in the table below. Use these d swer the questions below the table. rug Unhappy/ Moderately Happy/Delighted Tot Miserable Happy Satisfaction ethidine 5 9 6 20 lorphine 9 9 2 20 Total 14 18 40 Pain ethidine 2 10 8 20 lorphine 2 8 10 20 Total 4 18 18 40