This is the example that I tried to do in class last night which had two mistakes on it. I fixed the mistakes and the data (and my summary statistics) are provided below. The example is about establishing a p-chart for complications developed after open heart surgery in a hospital. Data is collected monthly. We want to know whether the complication rates have been in control (or out-of-control) during this period. Here is the data you need

Month Comp. Procedure

1 14 105

2 12 97

3 10 111

4 12 100

5 9 95

6 7 111

7 9 68

8 11 47

9 9 83

10 12 108

11 10 115

12 7 94

13 12 107

14 9 99

15 15 105

16 13 110

17 7 97

18 10 105

19 8 71

20 5 48

21 12 95

22 9 110

23 7 103

24 9 95

25 15 105

26 12 100

27 8 116

28 2 110

29 9 105

30 10 120

Total 294 2935

Using the average complication rate as the baseline, what is the minimum sample size is required to this study?

Do you adequate sample sizes for this study?

3c. List the months during which the sample size was/were NOT adequate?

Contrast p-chart (with all the zones) based on average sample

Is the process in control? (use the Short Rule from hand-out to answer this question)