In: Statistics and Probability
1. The following data was collected in a clinical trial evaluating a new compound designed to improve wound healing in trauma patients. The new compound was compared against a placebo. After treatment for 5 days with the new compound or placebo, the extent of wound healing was measured and the data are shown below
Percent Wound Healing |
||||
Treatment |
0-25% |
26-50% |
51-75% |
76-100% |
New Compound (n=125) |
15 |
37 |
32 |
41 |
Placebo (n=125) |
36 |
45 |
34 |
10 |
Is there a difference in the extent of wound healing by treatment? (Hint: Are treatment and the percent wound healing independent?) Run the appropriate test at a 5% level of significance.
2. Use the data in Problem #1 and pool the data across the treatments into one sample of size n=250. Use the pooled data to test whether the distribution of the percent wound healing is approximately normal. Specifically, use the following distribution: 30%, 40%, 20% and 10% and a=0.05 to run the appropriate test.
Percent Wound Healing |
|||||
Treatment |
0-25% |
26-50% |
51-75% |
76-100% |
Total |
Number of Patients |
51 |
82 |
66 |
51 |
250 |