Create Attribute Control Charts Chapter 7
Figure07-01
Chapter 7 - Statistical Process Control for Monitoring Failure Rates | ||||||||
AMI, aspirin administrered at arrival, n = 20 | ||||||||
Figure 7.1 – Indicators of Unstable Systems | ||||||||
Sample | # | p | Ctr Line | UCLp | LCLp | |||
Sample 1 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
2 | 3 | 0.15 | 0.0875 | 0.2771 | 0.0000 | |||
3 | 4 | 0.20 | 0.0875 | 0.2771 | 0.0000 | |||
4 | 3 | 0.15 | 0.0875 | 0.2771 | 0.0000 | |||
5 | 2 | 0.10 | 0.0875 | 0.2771 | 0.0000 | |||
6 | 0 | 0.00 | 0.0875 | 0.2771 | 0.0000 | |||
7 | 3 | 0.15 | 0.0875 | 0.2771 | 0.0000 | |||
8 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
9 | 0 | 0.00 | 0.0875 | 0.2771 | 0.0000 | |||
10 | 4 | 0.20 | 0.0875 | 0.2771 | 0.0000 | |||
11 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
12 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
13 | 0 | 0.00 | 0.0875 | 0.2771 | 0.0000 | |||
14 | 2 | 0.10 | 0.0875 | 0.2771 | 0.0000 | |||
15 | 2 | 0.10 | 0.0875 | 0.2771 | 0.0000 | |||
16 | 4 | 0.20 | 0.0875 | 0.2771 | 0.0000 | |||
17 | 0 | 0.00 | 0.0875 | 0.2771 | 0.0000 | stable | ||
18 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
Sample 19 | 0 | 0.00 | 0.0875 | 0.2771 | 0.0000 | |||
20 | 3 | 0.15 | 0.0875 | 0.2771 | 0.0000 | |||
Total | 35 | |||||||
pbar | 0.0875 | |||||||
Sample | # | p | Ctr Line | UCLp | LCLp | |||
Sample 1 | 2 | 0.10 | 0.0875 | 0.2771 | 0.0000 | |||
2 | 3 | 0.15 | 0.0875 | 0.2771 | 0.0000 | |||
3 | 6 | 0.30 | 0.0875 | 0.2771 | 0.0000 | |||
4 | 4 | 0.20 | 0.0875 | 0.2771 | 0.0000 | |||
5 | 4 | 0.20 | 0.0875 | 0.2771 | 0.0000 | |||
6 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
7 | 0 | 0.00 | 0.0875 | 0.2771 | 0.0000 | |||
8 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
9 | 2 | 0.10 | 0.0875 | 0.2771 | 0.0000 | |||
10 | 0 | 0.00 | 0.0875 | 0.2771 | 0.0000 | |||
11 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
12 | 0 | 0.00 | 0.0875 | 0.2771 | 0.0000 | |||
13 | 2 | 0.10 | 0.0875 | 0.2771 | 0.0000 | |||
14 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
15 | 4 | 0.20 | 0.0875 | 0.2771 | 0.0000 | |||
16 | 0 | 0.00 | 0.0875 | 0.2771 | 0.0000 | |||
17 | 3 | 0.15 | 0.0875 | 0.2771 | 0.0000 | |||
18 | 0 | 0.00 | 0.0875 | 0.2771 | 0.0000 | unstable breaches ucl in period 3 | ||
Sample 19 | 0 | 0.00 | 0.0875 | 0.2771 | 0.0000 | |||
20 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
Total | 35 | |||||||
pbar | 0.0875 | |||||||
Sample | # | p | Ctr Line | UCLp | LCLp | |||
Sample 1 | 2 | 0.10 | 0.0875 | 0.2771 | 0.0000 | |||
2 | 2 | 0.10 | 0.0875 | 0.2771 | 0.0000 | |||
3 | 0 | 0.00 | 0.0875 | 0.2771 | 0.0000 | |||
4 | 3 | 0.15 | 0.0875 | 0.2771 | 0.0000 | |||
5 | 2 | 0.10 | 0.0875 | 0.2771 | 0.0000 | |||
6 | 0 | 0.00 | 0.0875 | 0.2771 | 0.0000 | |||
7 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
8 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
9 | 0 | 0.00 | 0.0875 | 0.2771 | 0.0000 | |||
10 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
11 | 0 | 0.00 | 0.0875 | 0.2771 | 0.0000 | |||
12 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
13 | 2 | 0.10 | 0.0875 | 0.2771 | 0.0000 | |||
14 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
15 | 2 | 0.10 | 0.0875 | 0.2771 | 0.0000 | |||
16 | 3 | 0.15 | 0.0875 | 0.2771 | 0.0000 | |||
17 | 2 | 0.10 | 0.0875 | 0.2771 | 0.0000 | |||
18 | 4 | 0.20 | 0.0875 | 0.2771 | 0.0000 | trend, upward starting in period 11 - unstable | ||
Sample 19 | 3 | 0.15 | 0.0875 | 0.2771 | 0.0000 | |||
20 | 5 | 0.25 | 0.0875 | 0.2771 | 0.0000 | |||
Total | 35 | |||||||
pbar | 0.0875 | |||||||
Sample | # | p | Ctr Line | UCLp | LCLp | |||
Sample 1 | 4 | 0.20 | 0.0875 | 0.2771 | 0.0000 | |||
2 | 2 | 0.10 | 0.0875 | 0.2771 | 0.0000 | |||
3 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
4 | 3 | 0.15 | 0.0875 | 0.2771 | 0.0000 | |||
5 | 4 | 0.20 | 0.0875 | 0.2771 | 0.0000 | |||
6 | 2 | 0.10 | 0.0875 | 0.2771 | 0.0000 | |||
7 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
8 | 4 | 0.20 | 0.0875 | 0.2771 | 0.0000 | |||
9 | 4 | 0.20 | 0.0875 | 0.2771 | 0.0000 | |||
10 | 3 | 0.15 | 0.0875 | 0.2771 | 0.0000 | |||
11 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
12 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
13 | 0 | 0.00 | 0.0875 | 0.2771 | 0.0000 | |||
14 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
15 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
16 | 0 | 0.00 | 0.0875 | 0.2771 | 0.0000 | |||
17 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
18 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | series of points below (above) the centerline, indicates change in the system | ||
Sample 19 | 0 | 0.00 | 0.0875 | 0.2771 | 0.0000 | unstable | ||
20 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
Total | 35 | |||||||
pbar | 0.0875 | |||||||
Sample | # | p | Ctr Line | UCLp | LCLp | |||
Sample 1 | 3 | 0.15 | 0.0875 | 0.2771 | 0.0000 | |||
2 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
3 | 2 | 0.10 | 0.0875 | 0.2771 | 0.0000 | |||
4 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
5 | 3 | 0.15 | 0.0875 | 0.2771 | 0.0000 | |||
6 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
7 | 2 | 0.10 | 0.0875 | 0.2771 | 0.0000 | |||
8 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
9 | 2 | 0.10 | 0.0875 | 0.2771 | 0.0000 | |||
10 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
11 | 3 | 0.15 | 0.0875 | 0.2771 | 0.0000 | |||
12 | 0 | 0.00 | 0.0875 | 0.2771 | 0.0000 | |||
13 | 3 | 0.15 | 0.0875 | 0.2771 | 0.0000 | |||
14 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
15 | 2 | 0.10 | 0.0875 | 0.2771 | 0.0000 | |||
16 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
17 | 3 | 0.15 | 0.0875 | 0.2771 | 0.0000 | |||
18 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
Sample 19 | 3 | 0.15 | 0.0875 | 0.2771 | 0.0000 | pattern, unstable, could be result of different staff, equipment | ||
20 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
Total | 35 | |||||||
pbar | 0.0875 | |||||||
Sample | # | p | Ctr Line | UCLp | LCLp | |||
Sample 1 | 4 | 0.20 | 0.0875 | 0.2771 | 0.0000 | |||
2 | 4 | 0.20 | 0.0875 | 0.2771 | 0.0000 | |||
3 | 4 | 0.20 | 0.0875 | 0.2771 | 0.0000 | |||
4 | 4 | 0.20 | 0.0875 | 0.2771 | 0.0000 | |||
5 | 4 | 0.20 | 0.0875 | 0.2771 | 0.0000 | |||
6 | 4 | 0.20 | 0.0875 | 0.2771 | 0.0000 | |||
7 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
8 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
9 | 0 | 0.00 | 0.0875 | 0.2771 | 0.0000 | |||
10 | 2 | 0.10 | 0.0875 | 0.2771 | 0.0000 | |||
11 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
12 | 0 | 0.00 | 0.0875 | 0.2771 | 0.0000 | |||
13 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
14 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
15 | 0 | 0.00 | 0.0875 | 0.2771 | 0.0000 | |||
16 | 0 | 0.00 | 0.0875 | 0.2771 | 0.0000 | |||
17 | 2 | 0.10 | 0.0875 | 0.2771 | 0.0000 | |||
18 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | |||
Sample 19 | 0 | 0.00 | 0.0875 | 0.2771 | 0.0000 | |||
20 | 1 | 0.05 | 0.0875 | 0.2771 | 0.0000 | unstable, series of points close to an upper or lower limits. | ||
Total | 35 | |||||||
pbar | 0.0875 |
Figure07-01
p
Ctr Line
UCLp
LCLp
Failure Rate
Stable System
Figure07-02
p
Ctr Line
UCLp
LCLp
Failure Rate
Control Limit Breach
Figure07-03
p
Ctr Line
UCLp
LCLp
Failure Rate
Upward Trend
Figure07-04
p
Ctr Line
UCLp
LCLp
Failure Rates
Series on One Side of Center Line
Figure07-05
p
Ctr Line
UCLp
LCLp
Failure Rate
Pattern
Figure07-06
p
Ctr Line
UCLp
LCLp
Failure Rate
Series Close to Control Limit
Figure07-07
Chapter 7 - Statistical Process Control for Monitoring Failure Rates | |||||||||
Table 7.2 – Errors in Surgical Coding | |||||||||
Figure 7.2 – p chart | |||||||||
Sample | Non-conforming | sample | p | CL | UCLp | LCLp | |||
Jan | 2 | 50 | 4% | 0.0683 | 0.1754 | 0.0000 | |||
Feb | 3 | 50 | 6% | 0.0683 | 0.1754 | 0.0000 | |||
Mar | 1 | 50 | 2% | 0.0683 | 0.1754 | 0.0000 | |||
Apr | 2 | 50 | 4% | 0.0683 | 0.1754 | 0.0000 | |||
May | 3 | 50 | 6% | 0.0683 | 0.1754 | 0.0000 | |||
Jun | 1 | 50 | 2% | 0.0683 | 0.1754 | 0.0000 | |||
Jul | 11 | 50 | 22% | 0.0683 | 0.1754 | 0.0000 | |||
Aug | 7 | 50 | 14% | 0.0683 | 0.1754 | 0.0000 | |||
Sep | 5 | 50 | 10% | 0.0683 | 0.1754 | 0.0000 | |||
Oct | 2 | 50 | 4% | 0.0683 | 0.1754 | 0.0000 | |||
Nov | 3 | 50 | 6% | 0.0683 | 0.1754 | 0.0000 | |||
Dec | 1 | 50 | 2% | 0.0683 | 0.1754 | 0.0000 | |||
Total | 41 | 600 | |||||||
pbar | 0.0683 | ||||||||
1 | |||||||||
incorrect | sample | p | CLst | UCLst | LCLst | Clun | UCLun | LCLun | |
Jan | 2 | 50 | 4% | 1 | 1 | 0 | 0.0683333333 | 0.1753823875 | 0 |
Feb | 3 | 50 | 6% | 1 | 1 | 0 | 0.0683333333 | 0.1753823875 | 0 |
Mar | 1 | 50 | 2% | 1 | 1 | 0 | 0.0683333333 | 0.1753823875 | 0 |
Apr | 2 | 50 | 4% | 1 | 1 | 0 | 0.0683333333 | 0.1753823875 | 0 |
May | 3 | 50 | 6% | 1 | 1 | 0 | 0.0683333333 | 0.1753823875 | 0 |
Jun | 1 | 50 | 2% | 1 | 1 | 0 | 0.0683333333 | 0.1753823875 | 0 |
Jul | 1 | 1 | 0 | 0.0683333333 | 0.1753823875 | 0 | |||
Aug | 7 | 50 | 14% | 1 | 1 | 0 | 0.0683333333 | 0.1753823875 | 0 |
Sep | 5 | 50 | 10% | 1 | 1 | 0 | 0.0683333333 | 0.1753823875 | 0 |
Oct | 2 | 50 | 4% | 1 | 1 | 0 | 0.0683333333 | 0.1753823875 | 0 |
Nov | 3 | 50 | 6% | 1 | 1 | 0 | 0.0683333333 | 0.1753823875 | 0 |
Dec | 1 | 50 | 2% | 1 | 1 | 0 | 0.0683333333 | 0.1753823875 | 0 |
30 | 600 | ||||||||
0.05 |
Figure07-07
0.04 | 0.0683333333 | 0.1753823875 | 0 |
0.06 | 0.0683333333 | 0.1753823875 | 0 |
0.02 | 0.0683333333 | 0.1753823875 | 0 |
0.04 | 0.0683333333 | 0.1753823875 | 0 |
0.06 | 0.0683333333 | 0.1753823875 | 0 |
0.02 | 0.0683333333 | 0.1753823875 | 0 |
0.22 | 0.0683333333 | 0.1753823875 | 0 |
0.14 | 0.0683333333 | 0.1753823875 | 0 |
0.1 | 0.0683333333 | 0.1753823875 | 0 |
0.04 | 0.0683333333 | 0.1753823875 | 0 |
0.06 | 0.0683333333 | 0.1753823875 | 0 |
0.02 | 0.0683333333 | 0.1753823875 | 0 |
p
CL
UCL
LCL
% Claims with Errors
Surgical Coding Accuracy
Figure07-08
0.04 | 0.05 | 0.14246621 | 0 | 0.0683333333 | 0.1753823875 | 0 |
0.06 | 0.05 | 0.14246621 | 0 | 0.0683333333 | 0.1753823875 | 0 |
0.02 | 0.05 | 0.14246621 | 0 | 0.0683333333 | 0.1753823875 | 0 |
0.04 | 0.05 | 0.14246621 | 0 | 0.0683333333 | 0.1753823875 | 0 |
0.06 | 0.05 | 0.14246621 | 0 | 0.0683333333 | 0.1753823875 | 0 |
0.02 | 0.05 | 0.14246621 | 0 | 0.0683333333 | 0.1753823875 | 0 |
0.05 | 0.14246621 | 0 | 0.0683333333 | 0.1753823875 | 0 | |
0.14 | 0.05 | 0.14246621 | 0 | 0.0683333333 | 0.1753823875 | 0 |
0.1 | 0.05 | 0.14246621 | 0 | 0.0683333333 | 0.1753823875 | 0 |
0.04 | 0.05 | 0.14246621 | 0 | 0.0683333333 | 0.1753823875 | 0 |
0.06 | 0.05 | 0.14246621 | 0 | 0.0683333333 | 0.1753823875 | 0 |
0.02 | 0.05 | 0.14246621 | 0 | 0.0683333333 | 0.1753823875 | 0 |
p
CLst
UCLst
LCLst
Clun
UCLun
LCLun
% Claims with Errors
Surgical Coding Accuracy without July
Figure07-09
Chapter 7 - Statistical Process Control for Monitoring Failure Rates | ||||||
Figure 7.3– np chart | ||||||
Sample | Non-conforming | CL | UCLp | LCLp | ||
2011 Jan | 2 | 3.4167 | 8.7691 | 0.0000 | ||
Feb | 3 | 3.4167 | 8.7691 | 0.0000 | ||
Mar | 1 | 3.4167 | 8.7691 | 0.0000 | ||
Apr | 2 | 3.4167 | 8.7691 | 0.0000 | ||
May | 3 | 3.4167 | 8.7691 | 0.0000 | ||
Jun | 1 | 3.4167 | 8.7691 | 0.0000 | ||
Jul | 11 | 3.4167 | 8.7691 | 0.0000 | ||
Aug | 7 | 3.4167 | 8.7691 | 0.0000 | ||
Sep | 5 | 3.4167 | 8.7691 | 0.0000 | ||
Oct | 2 | 3.4167 | 8.7691 | 0.0000 | ||
Nov | 3 | 3.4167 | 8.7691 | 0.0000 | ||
Dec | 1 | 3.4167 | 8.7691 | 0.0000 | ||
Total | 41 | |||||
p bar | 0.0683 | |||||
npbar | 3.4167 |
Figure07-09
Non-conforming
CL
UCLp
LCLp
Number of Claims with Errors
Non-conforming Surgical Claims
Figure07-10
Chapter 7 - Statistical Process Control for Monitoring Failure Rates | |||||||
Table 7.3 – Heart Failure and Smoking Cessation | |||||||
Sample | p | Ctr Line | UCLp | LCLp | Figure 7.4 – Breach of Lower Control Limit | ||
2011 Jan | 0.50 | 0.3800 | 0.7056 | 0.0544 | |||
Feb | 0.45 | 0.3800 | 0.7056 | 0.0544 | |||
Mar | 0.60 | 0.3800 | 0.7056 | 0.0544 | |||
Apr | 0.55 | 0.3800 | 0.7056 | 0.0544 | |||
May | 0.40 | 0.3800 | 0.7056 | 0.0544 | |||
Jun | 0.55 | 0.3800 | 0.7056 | 0.0544 | |||
Jul | 0.45 | 0.3800 | 0.7056 | 0.0544 | |||
Aug | 0.50 | 0.3800 | 0.7056 | 0.0544 | |||
Sep | 0.40 | 0.3800 | 0.7056 | 0.0544 | |||
Oct | 0.30 | 0.3800 | 0.7056 | 0.0544 | |||
Nov | 0.35 | 0.3800 | 0.7056 | 0.0544 | |||
Dec | 0.40 | 0.3800 | 0.7056 | 0.0544 | |||
2012 Jan | 0.30 | 0.3800 | 0.7056 | 0.0544 | |||
Feb | 0.45 | 0.3800 | 0.7056 | 0.0544 | |||
Mar | 0.35 | 0.3800 | 0.7056 | 0.0544 | |||
Apr | 0.40 | 0.3800 | 0.7056 | 0.0544 | |||
May | 0.25 | 0.3800 | 0.7056 | 0.0544 | |||
Jun | 0.40 | 0.3800 | 0.7056 | 0.0544 | |||
Jul | 0.00 | 0.3800 | 0.7056 | 0.0544 | |||
Aug | 0.00 | 0.3800 | 0.7056 | 0.0544 | |||
pbar | 0.3800 |
Figure07-10
p
Ctr Line
UCLp
LCLp
% Smokers not receiving smoking cessation counseling
Heart Failure Treatment
Jan 2011 - Aug 2012
Problem07-03
Chapter 7 - Statistical Process Control for Monitoring Failure Rates | |||||||||||
Figure 7.5 – Establishing Valid Control Limits | |||||||||||
Sample | Non-conforming | sample | p | Ctrline valid | UCL valid | LCL Valid | Ctrline invalid | UCL invalid | LCL invalid | ||
Jan | 2 | 50 | 4% | 0.0545 | 0.1509 | 0.0000 | 0.0683 | 0.1754 | 0.0000 | ||
Feb | 3 | 50 | 6% | 0.0545 | 0.1509 | 0.0000 | 0.0683 | 0.1754 | 0.0000 | ||
Mar | 1 | 50 | 2% | 0.0545 | 0.1509 | 0.0000 | 0.0683 | 0.1754 | 0.0000 | ||
Apr | 2 | 50 | 4% | 0.0545 | 0.1509 | 0.0000 | 0.0683 | 0.1754 | 0.0000 | ||
May | 3 | 50 | 6% | 0.0545 | 0.1509 | 0.0000 | 0.0683 | 0.1754 | 0.0000 | ||
Jun | 1 | 50 | 2% | 0.0545 | 0.1509 | 0.0000 | 0.0683 | 0.1754 | 0.0000 | ||
Jul | 0.0545 | 0.1509 | 0.0000 | 0.0683 | 0.1754 | 0.0000 | |||||
Aug | 7 | 50 | 14% | 0.0545 | 0.1509 | 0.0000 | 0.0683 | 0.1754 | 0.0000 | ||
Sep | 5 | 50 | 10% | 0.0545 | 0.1509 | 0.0000 | 0.0683 | 0.1754 | 0.0000 | ||
Oct | 2 | 50 | 4% | 0.0545 | 0.1509 | 0.0000 | 0.0683 | 0.1754 | 0.0000 | ||
Nov | 3 | 50 | 6% | 0.0545 | 0.1509 | 0.0000 | 0.0683 | 0.1754 | 0.0000 | ||
Dec | 1 | 50 | 2% | 0.0545 | 0.1509 | 0.0000 | 0.0683 | 0.1754 | 0.0000 | ||
Total | 30 | 550 | |||||||||
pbar | 0.0545 |
Problem07-03
p
Ctrline valid
UCL valid
LCL Valid
Ctrline invalid
UCL invalid
LCL invalid
% Claims with Errors
Valid Control Limits without Special Cause Variation
Problem07-04
Chapter 7 - Statistical Process Control for Monitoring Failure Rates | |||||||||
Table 7.4 (A) – Constant Control Limits Based on Average Sample Size | |||||||||
Month | Errors | n | p | Ctr Line | UCLp | LCLp | |||
Jan | 2 | 45 | 0.0444 | 0.0683 | 0.1754 | 0.0000 | |||
Feb | 3 | 55 | 0.0545 | 0.0683 | 0.1754 | 0.0000 | Figure 7.6 (A) – Constant Control Limits | ||
Mar | 1 | 50 | 0.0200 | 0.0683 | 0.1754 | 0.0000 | |||
Apr | 2 | 48 | 0.0417 | 0.0683 | 0.1754 | 0.0000 | |||
May | 3 | 52 | 0.0577 | 0.0683 | 0.1754 | 0.0000 | |||
Jun | 1 | 44 | 0.0227 | 0.0683 | 0.1754 | 0.0000 | |||
Jul | 11 | 52 | 0.2115 | 0.0683 | 0.1754 | 0.0000 | |||
Aug | 7 | 53 | 0.1321 | 0.0683 | 0.1754 | 0.0000 | |||
Sep | 5 | 51 | 0.0980 | 0.0683 | 0.1754 | 0.0000 | |||
Oct | 2 | 48 | 0.0417 | 0.0683 | 0.1754 | 0.0000 | |||
Nov | 3 | 52 | 0.0577 | 0.0683 | 0.1754 | 0.0000 | |||
Dec | 1 | 50 | 0.0200 | 0.0683 | 0.1754 | 0.0000 | |||
41 | 50 | ||||||||
pbar | 0.0683 | ||||||||
Table 7.4 (B) – Variable Control Limits Based on Period Specific Sample Size | |||||||||
Errors | n | p | Ctrline | UCL | LCL | ||||
Month | 2 | 45 | 0.0444 | 0.0683 | 0.1812 | 0.0000 | |||
Jan | 3 | 55 | 0.0545 | 0.0683 | 0.1704 | 0.0000 | Min | ||
Feb | 1 | 50 | 0.0200 | 0.0683 | 0.1754 | 0.0000 | |||
Mar | 2 | 48 | 0.0417 | 0.0683 | 0.1776 | 0.0000 | Figure 7.6 (B) – Variable Control Limits | ||
Apr | 3 | 52 | 0.0577 | 0.0683 | 0.1733 | 0.0000 | |||
May | 1 | 44 | 0.0227 | 0.0683 | 0.1824 | 0.0000 | Max | ||
Jun | 11 | 52 | 0.2115 | 0.0683 | 0.1733 | 0.0000 | |||
Jul | 7 | 53 | 0.1321 | 0.0683 | 0.1723 | 0.0000 | |||
Aug | 5 | 51 | 0.0980 | 0.0683 | 0.1743 | 0.0000 | |||
Sep | 2 | 48 | 0.0417 | 0.0683 | 0.1776 | 0.0000 | |||
Oct | 3 | 52 | 0.0577 | 0.0683 | 0.1733 | 0.0000 | |||
Nov | 1 | 50 | 0.0200 | 0.0683 | 0.1754 | 0.0000 | |||
Dec | |||||||||
UCLp | |||||||||
Maximum | 0.1824 | ||||||||
Minimum | 0.1704 | ||||||||
Difference | 0.0120 |
Problem07-04
p
Ctr Line
UCLp
LCLp
% Claims with errors
Constant Control Limits
Problem07-05
p
Ctrline
UCL
LCL
% Claims with errors
Variable Control Limits
Chapter 7 - Statistical Process Control for Monitoring Failure Rates | |||||||||
Table 7.5 – Aspirin Administration among AMI Patients | |||||||||
Month | Not Given | n | p | Ctr line | UCLp | LCLp | Figure 7.7 – p chart for Aspirin Delivery to AMI Patients | ||
Jan | 2 | 10 | 0.20 | 0.1688 | 0.5241 | 0.0000 | |||
Feb | 3 | 10 | 0.30 | 0.1688 | 0.5241 | 0.0000 | |||
Mar | 2 | 10 | 0.20 | 0.1688 | 0.5241 | 0.0000 | |||
Apr | 4 | 10 | 0.40 | 0.1688 | 0.5241 | 0.0000 | |||
May | 3 | 10 | 0.30 | 0.1688 | 0.5241 | 0.0000 | |||
Jun | 3 | 10 | 0.30 | 0.1688 | 0.5241 | 0.0000 | |||
Jul | 2 | 10 | 0.20 | 0.1688 | 0.5241 | 0.0000 | |||
Aug | 3 | 10 | 0.30 | 0.1688 | 0.5241 | 0.0000 | |||
Sep | 1 | 10 | 0.10 | 0.1688 | 0.5241 | 0.0000 | |||
Oct | 0 | 10 | 0.00 | 0.1688 | 0.5241 | 0.0000 | |||
Nov | 1 | 10 | 0.10 | 0.1688 | 0.5241 | 0.0000 | |||
Dec | 1 | 10 | 0.10 | 0.1688 | 0.5241 | 0.0000 | |||
Jan | 0 | 10 | 0.00 | 0.1688 | 0.5241 | 0.0000 | |||
Feb | 1 | 10 | 0.10 | 0.1688 | 0.5241 | 0.0000 | |||
Mar | 0 | 10 | 0.00 | 0.1688 | 0.5241 | 0.0000 | |||
Apr | 1 | 10 | 0.10 | 0.1688 | 0.5241 | 0.0000 | |||
Total | 27 | 160 | |||||||
pbar | 0.1688 | ||||||||
UCLp | 0.5241 | ||||||||
LCLp | -0.1866 |
0.2 | 0.16875 | 0.5240612632 | 0 |
0.3 | 0.16875 | 0.5240612632 | 0 |
0.2 | 0.16875 | 0.5240612632 | 0 |
0.4 | 0.16875 | 0.5240612632 | 0 |
0.3 | 0.16875 | 0.5240612632 | 0 |
0.3 | 0.16875 | 0.5240612632 | 0 |
0.2 | 0.16875 | 0.5240612632 | 0 |
0.3 | 0.16875 | 0.5240612632 | 0 |
0.1 | 0.16875 | 0.5240612632 | 0 |
0 | 0.16875 | 0.5240612632 | 0 |
0.1 | 0.16875 | 0.5240612632 | 0 |
0.1 | 0.16875 | 0.5240612632 | 0 |
0 | 0.16875 | 0.5240612632 | 0 |
0.1 | 0.16875 | 0.5240612632 | 0 |
0 | 0.16875 | 0.5240612632 | 0 |
0.1 | 0.16875 | 0.5240612632 | 0 |
p
Ctrline
UCL
LCL
% Not Delivered within 2 hrs
Control Limits for Aspirin Administration
% Not Delivered within 2 hrs
Rebased Control Limits for Aspirin Administration
Chapter 7 - Statistical Process Control for Monitoring Failure Rates | |||||||||
Table 7.5 – Aspirin Administration among AMI Patients | |||||||||
Month | Not Given | n | p | Ctr line | UCLp | LCLp | Figure 7.7 – p chart for Aspirin Delivery to AMI Patients (for comparison to figure 7.8) | ||
Jan | 2 | 10 | 0.20 | 0.1688 | 0.5241 | 0.0000 | |||
Feb | 3 | 10 | 0.30 | 0.1688 | 0.5241 | 0.0000 | |||
Mar | 2 | 10 | 0.20 | 0.1688 | 0.5241 | 0.0000 | |||
Apr | 4 | 10 | 0.40 | 0.1688 | 0.5241 | 0.0000 | |||
May | 3 | 10 | 0.30 | 0.1688 | 0.5241 | 0.0000 | |||
Jun | 3 | 10 | 0.30 | 0.1688 | 0.5241 | 0.0000 | |||
Jul | 2 | 10 | 0.20 | 0.1688 | 0.5241 | 0.0000 | |||
Aug | 3 | 10 | 0.30 | 0.1688 | 0.5241 | 0.0000 | |||
Sep | 1 | 10 | 0.10 | 0.1688 | 0.5241 | 0.0000 | |||
Oct | 0 | 10 | 0.00 | 0.1688 | 0.5241 | 0.0000 | |||
Nov | 1 | 10 | 0.10 | 0.1688 | 0.5241 | 0.0000 | |||
Dec | 1 | 10 | 0.10 | 0.1688 | 0.5241 | 0.0000 | |||
Jan | 0 | 10 | 0.00 | 0.1688 | 0.5241 | 0.0000 | |||
Feb | 1 | 10 | 0.10 | 0.1688 | 0.5241 | 0.0000 | |||
Mar | 0 | 10 | 0.00 | 0.1688 | 0.5241 | 0.0000 | |||
Apr | 1 | 10 | 0.10 | 0.1688 | 0.5241 | 0.0000 | |||
Total | 27 | 160 | |||||||
pbar | 0.1688 | ||||||||
UCLp | 0.5241 | ||||||||
LCLp | -0.1866 | ||||||||
periods 1-8 | 0.2750 | ||||||||
UCLp 1-8 | 0.6986 | ||||||||
LCLp 1-8 | -0.1486 | ||||||||
Figure 7.8 – Rebased Control Limits for Aspirin Delivery to AMI Patients | |||||||||
periods 9-16 | 0.0625 | ||||||||
UCLp 9-16 | 0.2921 | ||||||||
LCLp 9-16 | -0.1671 | ||||||||
Rebased Control Limits | p | Ctr line | UCLp | LCLp | |||||
Jan | 0.20 | 0.2750 | 0.6986 | 0.0000 | |||||
Feb | 0.30 | 0.2750 | 0.6986 | 0.0000 | |||||
Mar | 0.20 | 0.2750 | 0.6986 | 0.0000 | |||||
Apr | 0.40 | 0.2750 | 0.6986 | 0.0000 | |||||
May | 0.30 | 0.2750 | 0.6986 | 0.0000 | |||||
Jun | 0.30 | 0.2750 | 0.6986 | 0.0000 | |||||
Jul | 0.20 | 0.2750 | 0.6986 | 0.0000 | |||||
Aug | 0.30 | 0.2750 | 0.6986 | 0.0000 | |||||
Sep | 0.10 | 0.0625 | 0.2921 | 0.0000 | |||||
Oct | 0.00 | 0.0625 | 0.2921 | 0.0000 | |||||
Nov | 0.10 | 0.0625 | 0.2921 | 0.0000 | |||||
Dec | 0.10 | 0.0625 | 0.2921 | 0.0000 | |||||
Jan | 0.00 | 0.0625 | 0.2921 | 0.0000 | |||||
Feb | 0.10 | 0.0625 | 0.2921 | 0.0000 | |||||
Mar | 0.00 | 0.0625 | 0.2921 | 0.0000 | |||||
Apr | 0.10 | 0.0625 | 0.2921 | 0.0000 |
0.2 | 0.16875 | 0.5240612632 | 0 |
0.3 | 0.16875 | 0.5240612632 | 0 |
0.2 | 0.16875 | 0.5240612632 | 0 |
0.4 | 0.16875 | 0.5240612632 | 0 |
0.3 | 0.16875 | 0.5240612632 | 0 |
0.3 | 0.16875 | 0.5240612632 | 0 |
0.2 | 0.16875 | 0.5240612632 | 0 |
0.3 | 0.16875 | 0.5240612632 | 0 |
0.1 | 0.16875 | 0.5240612632 | 0 |
0 | 0.16875 | 0.5240612632 | 0 |
0.1 | 0.16875 | 0.5240612632 | 0 |
0.1 | 0.16875 | 0.5240612632 | 0 |
0 | 0.16875 | 0.5240612632 | 0 |
0.1 | 0.16875 | 0.5240612632 | 0 |
0 | 0.16875 | 0.5240612632 | 0 |
0.1 | 0.16875 | 0.5240612632 | 0 |
p
Ctrline
UCL
LCL
% Not Delivered within 2 hrs
Control Limits for Aspirin Administration
p
Ctr line
UCLp
LCLp
% Not Delivered within 2 hrs
Rebased Control Limits for Aspirin Administration
Chapter 7 - Statistical Process Control for Monitoring Failure Rates | |||||||||
Duclos et al. (2009) | |||||||||
Month | n=1114 | p | pbar | UCLp | LCLp | Figure 7.9 - Duclos et al. SPC Charts | |||
2006 Jan | 46 | 0.03 | 0.0738 | 0.1894 | 0.0000 | ||||
Feb | 49 | 0.08 | 0.0738 | 0.1858 | 0.0000 | ||||
Mar | 49 | 0.06 | 0.0738 | 0.1858 | 0.0000 | ||||
Apr | 46 | 0.07 | 0.0738 | 0.1894 | 0.0000 | ||||
May | 47 | 0.04 | 0.0738 | 0.1881 | 0.0000 | ||||
Jun | 48 | 0.12 | 0.0738 | 0.1869 | 0.0000 | ||||
Jul | 49 | 0.05 | 0.0738 | 0.1858 | 0.0000 | ||||
Aug | 42 | 0.04 | 0.0738 | 0.1947 | 0.0000 | ||||
Sep | 52 | 0.04 | 0.0738 | 0.1825 | 0.0000 | ||||
Oct | 52 | 0.08 | 0.0738 | 0.1825 | 0.0000 | ||||
Nov | 42 | 0.1 | 0.0738 | 0.1947 | 0.0000 | ||||
Dec | 46 | 0.13 | 0.0738 | 0.1894 | 0.0000 | ||||
2007 Jan | 48 | 0.09 | 0.0738 | 0.1869 | 0.0000 | ||||
Feb | 45 | 0.11 | 0.0738 | 0.1906 | 0.0000 | ||||
Mar | 46 | 0.11 | 0.0738 | 0.1894 | 0.0000 | ||||
Apr | 47 | 0.06 | 0.0738 | 0.1881 | 0.0000 | ||||
May | 46 | 0.03 | 0.0738 | 0.1894 | 0.0000 | ||||
Jun | 45 | 0.06 | 0.0738 | 0.1906 | 0.0000 | ||||
Jul | 46 | 0.18 | 0.0738 | 0.1894 | 0.0000 | ||||
Aug | 38 | 0.01 | 0.0738 | 0.2009 | 0.0000 | ||||
Sep | 44 | 0.12 | 0.0738 | 0.1920 | 0.0000 | ||||
Oct | 47 | 0.04 | 0.0738 | 0.1881 | 0.0000 | ||||
Nov | 48 | 0.04 | 0.0738 | 0.1869 | 0.0000 | ||||
Dec | 47 | 0.08 | 0.0738 | 0.1881 | 0.0000 | ||||
pbar | 0.0738 | ||||||||
Month | n=1114 | p | pbar | UCLp | LCLp | ||||
2006 Jan | 46 | 0.32 | 0.2092 | 0.3891 | 0.0293 | ||||
Feb | 49 | 0.17 | 0.2092 | 0.3835 | 0.0349 | ||||
Mar | 49 | 0.14 | 0.2092 | 0.3835 | 0.0349 | ||||
Apr | 46 | 0.19 | 0.2092 | 0.3891 | 0.0293 | ||||
May | 47 | 0.21 | 0.2092 | 0.3871 | 0.0312 | ||||
Jun | 48 | 0.22 | 0.2092 | 0.3853 | 0.0331 | ||||
Jul | 49 | 0.19 | 0.2092 | 0.3835 | 0.0349 | ||||
Aug | 42 | 0.21 | 0.2092 | 0.3974 | 0.0209 | ||||
Sep | 52 | 0.14 | 0.2092 | 0.3784 | 0.0400 | ||||
Oct | 52 | 0.17 | 0.2092 | 0.3784 | 0.0400 | ||||
Nov | 42 | 0.2 | 0.2092 | 0.3974 | 0.0209 | ||||
Dec | 46 | 0.19 | 0.2092 | 0.3891 | 0.0293 | ||||
2007 Jan | 48 | 0.22 | 0.2092 | 0.3853 | 0.0331 | ||||
Feb | 45 | 0.19 | 0.2092 | 0.3911 | 0.0273 | ||||
Mar | 46 | 0.2 | 0.2092 | 0.3891 | 0.0293 | ||||
Apr | 47 | 0.19 | 0.2092 | 0.3871 | 0.0312 | ||||
May | 46 | 0.33 | 0.2092 | 0.3891 | 0.0293 | ||||
Jun | 45 | 0.24 | 0.2092 | 0.3911 | 0.0273 | ||||
Jul | 46 | 0.4 | 0.2092 | 0.3891 | 0.0293 | ||||
Aug | 38 | 0.12 | 0.2092 | 0.4071 | 0.0112 | ||||
Sep | 44 | 0.26 | 0.2092 | 0.3931 | 0.0252 | ||||
Oct | 47 | 0.19 | 0.2092 | 0.3871 | 0.0312 | ||||
Nov | 48 | 0.19 | 0.2092 | 0.3853 | 0.0331 | ||||
Dec | 47 | 0.14 | 0.2092 | 0.3871 | 0.0312 | ||||
pbar | 0.2092 | ||||||||
Data reconstructed by the author. |
p
pbar
UCLp
LCLp
% Recurrent laryngeal nerve palsy
Duclos et al. Nerve Palsy
p
pbar
UCLp
LCLp
% Hypocalcaemia
Duclos et al. Hypocalcaemia
Chapter 7 - Statistical Process Control for Monitoring Failure Rates | ||||||||
Fasting & Gisvold (2003) | ||||||||
Month | n | p | pbar | UCLp | LCLp | |||
1997 Jan/Feb | 1501 | 0.0300 | 0.0250 | 0.0371 | 0.0129 | Figure 7.10 - Fasting and Gisvold SPC Charts | ||
Mar/Apr | 1545 | 0.0310 | 0.0250 | 0.0369 | 0.0131 | |||
May/Jun | 1522 | 0.0300 | 0.0250 | 0.0370 | 0.0130 | |||
Jul/Aug | 1401 | 0.0350 | 0.0250 | 0.0375 | 0.0125 | |||
Sep/Oct | 1623 | 0.0290 | 0.0250 | 0.0366 | 0.0134 | |||
Nov/Dec | 1512 | 0.0240 | 0.0250 | 0.0370 | 0.0130 | |||
1998 Jan/Feb | 1560 | 0.0290 | 0.0250 | 0.0369 | 0.0131 | |||
Mar/Apr | 1511 | 0.0260 | 0.0250 | 0.0370 | 0.0130 | |||
May/Jun | 1587 | 0.0320 | 0.0250 | 0.0368 | 0.0132 | |||
Jul/Aug | 1397 | 0.0370 | 0.0250 | 0.0375 | 0.0125 | |||
Sep/Oct | 1602 | 0.0230 | 0.0250 | 0.0367 | 0.0133 | |||
Nov/Dec | 1554 | 0.0310 | 0.0250 | 0.0369 | 0.0131 | |||
1999 Jan/Feb | 1559 | 0.0310 | 0.0250 | 0.0369 | 0.0131 | |||
Mar/Apr | 1548 | 0.0290 | 0.0250 | 0.0369 | 0.0131 | |||
May/Jun | 1601 | 0.0160 | 0.0250 | 0.0367 | 0.0133 | |||
Jul/Aug | 1405 | 0.0210 | 0.0250 | 0.0375 | 0.0125 | |||
Sep/Oct | 1697 | 0.0180 | 0.0250 | 0.0364 | 0.0136 | |||
Nov/Dec | 1322 | 0.0190 | 0.0250 | 0.0379 | 0.0121 | |||
2000 Jan/Feb | 1568 | 0.0140 | 0.0250 | 0.0368 | 0.0132 | |||
Mar/Apr | 1520 | 0.0250 | 0.0250 | 0.0370 | 0.0130 | |||
May/Jun | 1574 | 0.0220 | 0.0250 | 0.0368 | 0.0132 | |||
Jul/Aug | 1388 | 0.0190 | 0.0250 | 0.0376 | 0.0124 | |||
Sep/Oct | 1701 | 0.0220 | 0.0250 | 0.0364 | 0.0136 | |||
Nov/Dec | 1504 | 0.0260 | 0.0250 | 0.0371 | 0.0129 | |||
2001 Jan/Feb | 1578 | 0.0120 | 0.0250 | 0.0368 | 0.0132 | |||
Mar/Apr | 1539 | 0.0250 | 0.0250 | 0.0369 | 0.0131 | |||
May/Jun | 1521 | 0.0230 | 0.0250 | 0.0370 | 0.0130 | |||
Jul/Aug | 1426 | 0.0210 | 0.0250 | 0.0374 | 0.0126 | |||
Sep/Oct | 1624 | 0.0260 | 0.0250 | 0.0366 | 0.0134 | |||
Nov/Dec | 1589 | 0.0240 | 0.0250 | 0.0367 | 0.0133 | |||
Average | 1532.6 | 0.0250 | ||||||
Month | n | p | pbar | UCLp | LCLp | |||
1997 Jan/Feb | 1501 | 0.03 | 0.0298 | 0.0429 | 0.0129 | |||
Mar/Apr | 1545 | 0.031 | 0.0298 | 0.0428 | 0.0131 | |||
May/Jun | 1522 | 0.03 | 0.0298 | 0.0429 | 0.0130 | |||
Jul/Aug | 1401 | 0.035 | 0.0298 | 0.0434 | 0.0125 | |||
Sep/Oct | 1623 | 0.029 | 0.0298 | 0.0424 | 0.0134 | |||
Nov/Dec | 1512 | 0.024 | 0.0298 | 0.0429 | 0.0130 | |||
1998 Jan/Feb | 1560 | 0.029 | 0.0298 | 0.0427 | 0.0131 | |||
Mar/Apr | 1511 | 0.026 | 0.0298 | 0.0429 | 0.0130 | |||
May/Jun | 1587 | 0.032 | 0.0298 | 0.0426 | 0.0132 | |||
Jul/Aug | 1397 | 0.037 | 0.0298 | 0.0434 | 0.0125 | |||
Sep/Oct | 1602 | 0.023 | 0.0298 | 0.0425 | 0.0133 | |||
Nov/Dec | 1554 | 0.031 | 0.0298 | 0.0427 | 0.0131 | |||
1999 Jan/Feb | 1559 | 0.031 | 0.0298 | 0.0427 | 0.0131 | |||
Mar/Apr | 1548 | 0.029 | 0.0298 | 0.0427 | 0.0131 | |||
May/Jun | 1601 | 0.016 | 0.0208 | 0.0315 | 0.0101 | |||
Jul/Aug | 1405 | 0.021 | 0.0208 | 0.0322 | 0.0094 | |||
Sep/Oct | 1697 | 0.018 | 0.0208 | 0.0312 | 0.0104 | |||
Nov/Dec | 1322 | 0.019 | 0.0208 | 0.0326 | 0.0090 | |||
2000 Jan/Feb | 1568 | 0.014 | 0.0208 | 0.0316 | 0.0100 | |||
Mar/Apr | 1520 | 0.025 | 0.0208 | 0.0318 | 0.0098 | |||
May/Jun | 1574 | 0.022 | 0.0208 | 0.0316 | 0.0100 | |||
Jul/Aug | 1388 | 0.019 | 0.0208 | 0.0323 | 0.0093 | |||
Sep/Oct | 1701 | 0.022 | 0.0208 | 0.0312 | 0.0104 | |||
Nov/Dec | 1504 | 0.026 | 0.0208 | 0.0319 | 0.0098 | |||
2001 Jan/Feb | 1578 | 0.012 | 0.0208 | 0.0316 | 0.0100 | |||
Mar/Apr | 1539 | 0.025 | 0.0208 | 0.0317 | 0.0099 | |||
May/Jun | 1521 | 0.023 | 0.0208 | 0.0318 | 0.0098 | |||
Jul/Aug | 1426 | 0.021 | 0.0208 | 0.0322 | 0.0095 | |||
Sep/Oct | 1624 | 0.026 | 0.0208 | 0.0314 | 0.0102 | |||
Nov/Dec | 1589 | 0.024 | 0.0208 | 0.0316 | 0.0101 | |||
Control Limits 1997 to 1999 Mar/Apr | ||||||||
0.0297857143 | ||||||||
Control Limits 1999 May/Jun to 2001 | ||||||||
0.0208125 |
p
pbar
UCLp
LCLp
% Difficult Emergence
Fasting & Gisvold
p
pbar
UCLp
LCLp
% Difficult Emergence
Fasting & Gisvold - Rebased Limits
Chapter 7 - Statistical Process Control for Monitoring Failure Rates | |||
Problem 7.3 - Semmelweis | |||
Month | Births | Deaths | Rate |
Jan 1846 | 336 | 45 | 13.4 |
Feb | 293 | 53 | 18.1 |
March | 311 | 48 | 15.4 |
April | 253 | 48 | 19.0 |
May | 305 | 41 | 13.4 |
June | 266 | 27 | 10.2 |
July | 252 | 33 | 13.1 |
August | 216 | 39 | 18.1 |
September | 271 | 39 | 14.4 |
October | 254 | 38 | 15.0 |
November | 297 | 32 | 10.8 |
December | 298 | 16 | 5.4 |
Jan 1847 | 311 | 10 | 3.2 |
Feb | 312 | 6 | 1.9 |
March | 305 | 11 | 3.6 |
April | 312 | 57 | 18.3 |
May | 294 | 36 | 12.2 |
June** | 268 | 6 | 2.4 |
July | 250 | 3 | 1.2 |
August | 264 | 5 | 1.9 |
September | 262 | 12 | 5.2 |
October | 278 | 11 | 4.0 |
November | 246 | 11 | 4.5 |
December | 273 | 8 | 2.9 |
Jan 1848 | 283 | 10 | 3.5 |
Feb | 291 | 2 | 0.7 |
March | 276 | 0 | 0.0 |
April | 305 | 2 | 0.7 |
May | 313 | 3 | 1.0 |
June | 264 | 3 | 1.1 |
July | 269 | 1 | 0.4 |
August | 261 | 0 | 0.0 |
September | 312 | 3 | 1.0 |
October | 299 | 7 | 2.3 |
November | 310 | 9 | 2.9 |
December | 373 | 5 | 1.3 |
Source: Semmelweis I, 1983, The Etiology, Concept, and Prophylaxis of Childbed Fever, The University of Wisconsin Press, Madison WI (originally published 1860) pp. 85, 90-91. |
Chapter 7 - Statistical Process Control for Monitoring Failure Rates | |||||||||||||||||||||||||
Problem 4 - Surgical Infections | |||||||||||||||||||||||||
Sample | |||||||||||||||||||||||||
Patient | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 |
1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
2 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
3 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
4 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 |
5 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
6 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
7 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 |
8 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
9 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
10 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 |
11 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
12 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
13 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
14 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
15 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
16 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 |
17 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
18 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
19 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
20 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Chapter 7 - Statistical Process Control for Monitoring Failure Rates | ||
Problem 7.5 - Readmission Rates | ||
Month | Readmits | Sample |
Jan | 3 | 10 |
Feb | 3 | 10 |
Mar | 4 | 10 |
Apr | 3 | 8 |
May | 3 | 10 |
Jun | 3 | 9 |
Jul | 3 | 10 |
Aug | 3 | 9 |
Sep | 3 | 9 |
Oct | 3 | 10 |
Nov | 3 | 9 |
Dec | 2 | 10 |
Jan | 3 | 10 |
Feb | 2 | 8 |
Mar | 3 | 10 |
Apr | 2 | 9 |
May | 3 | 10 |
Jun | 2 | 9 |
Jul | 3 | 10 |
Aug | 3 | 10 |
Sep | 2 | 10 |
Oct | 2 | 10 |
Nov | 2 | 8 |
Dec | 2 | 9 |