| |
Total
|
Dead
|
CFR
|
CFR
|
X deaths
|
Y deaths
|
|---|
|
#
|
#
|
%
|
X/Y
|
%
|
%
|
|---|
|
Scenario A
|
|
X
|
500
|
0
|
0.0
| | | |
|
Y
|
1500
|
30
|
2.0
|
0.0
| | |
|
Both X & Y
|
500
|
30
|
6.0
| | | |
|
Total
|
2500
|
60
|
2.4
| | | |
|
All-X
|
1000
|
30
|
3.0
| |
50%
| |
|
All- Y
|
2000
|
60
|
3.0
|
1.0
| |
100%
|
|
Scenario B
|
|
X
|
500
|
6
|
1.2
| | | |
|
Y
|
1500
|
30
|
2.0
|
0.6
| | |
|
Both X & Y
|
500
|
30
|
6.0
| | | |
|
Total
|
2500
|
66
|
2.6
| | | |
|
All- X
|
1000
|
36
|
3.6
| |
55%
| |
|
All- Y
|
2000
|
60
|
3.0
|
1.2
| |
91%
|
|
Scenario C
|
|
X
|
500
|
10
|
2.0
| | | |
|
Y
|
1500
|
30
|
2.0
|
1.0
| | |
|
Both X & Y
|
500
|
30
|
6.0
| | | |
|
Total
|
2500
|
70
|
2.8
| | | |
|
All- X
|
1000
|
40
|
4.0
| |
57%
| |
|
All- Y
|
2000
|
60
|
3.0
|
1.3
| |
86%
|
- In Scenario A, X does not have any mortality by itself, but when the subjects with both criteria are included X and Y appear to have the same mortality rate. Using only criterion X would select those children with zero mortality and those with both X and Y criteria and miss all the deaths related to criterion Y
- In Scenario B, there is a lower mortality with criterion X, however when the subjects fulfilling both criteria are included the relative case fatality rates are reversed so it appears now that X is a superior diagnostic parameter than Y. Yet its use only identifies 55% of the deaths
- In Scenario C, both X and Y have the same mortality rates but when the subjects with both criteria are included Y appears to be a superior diagnostic criterion. Yet this only leads to identification of 57% of deaths
- The columns % deaths shows the percentage of all deaths that would occur in children with criterion X or criterion Y as the single diagnostic tool. Criterion Y identifies more deaths than criterion X, but when the children with both criteria are included criterion X appears to have a higher case fatality rate
