A clinical trial is run to investigate the

This preview shows page 8 - 11 out of 12 pages.

33. A clinical trial is run to investigate the effectiveness of an experimental drug in reducing preterm delivery to a drug considered standard care and to a placebo. Pregnant women are enrolled and randomly assigned to receive either the experimental drug, the standard drug or a placebo. Women are followed through delivery and classified as delivering preterm (< 37 weeks) or not. The data are shown below. Preterm Delivery Experimental Drug Standard Drug Placebo Yes 17 23 35 No 83 77 65 Is there a statistically significant difference in the proportions of women delivering preterm among the three treatment groups? Run the test at a 5% level of significance. 34. A study is run comparing HDL cholesterol levels between men who exercise regularly and those who do not. The data are shown below. Regular Exercise N Mean Std Dev Yes 35 48.5 12.5 No 120 56.9 11.9 Generate a 95% confidence interval for the difference in mean HDL levels between men who exercise regularly and those who do not. 35. Suppose a hypertension trial is mounted and 18 participants are randomly assigned to one of the comparison treatments. Each participant takes the assigned medication and his or her systolic blood pressure is recorded after 6 months on the assigned treatment. The data are as follows. Standard Treatment Placebo New Treatment 124 134 114 111 143 117 133 148 121 125 142 124 128 150 122 115 160 128
Is there a difference in mean systolic blood pressure among treatments? Run the appropriate test at α = 0.05. 36. A study is designed to investigate whether there is a difference in response to various treatments in patients with Rheumatoid arthritis. The outcome is the patient’s self-reported effect of treatment. The data are shown below. Is there a significant difference in effect of treatment? Run the test at a 5% level of significance. Symptoms Worsened No Effect Symptoms Improved Total Treatment 1 22 14 14 50 Treatment 2 14 15 21 50 Treatment 3 9 12 29 50 37. Using the data below, suppose we focus on the proportions of patients who show improvement. Is there a statistically significant difference in the proportions of patients who show improvement between treatments 1 and 2. Run the test at a 5% level of significance. Symptoms Worsened No Effect Symptoms Improved Total Treatment 1 22 14 14 50 Treatment 2 14 15 21 50 Treatment 3 9 12 29 50 38. An analysis is conducted to compare mean time to pain relief (measured in minutes) under four competing treatment regimens. Summary statistics on the four treatments are shown below. Treatment Sample Size Mean Time to Relief Sample Variance A 5 33.8 17.7
B 5 27.0 15.5 C 5 50.8 9.7 D 5 39.6 16.8 Complete the following ANOVA Table. Source of Variation SS df MS F Between Groups Within Groups 3719.4 8 Total

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture

  • Left Quote Icon

    Student Picture