|
Scenario 1 Prevalence 40%:
|
1-test
|
2
|
3920
|
60
|
80
|
0.985
| |
|
2-test
|
2 → 5
|
3842
|
1
|
158
|
1.000
|
3980
|
|
1-test
|
3
|
3980
|
120
|
20
|
0.971
| |
|
2-test
|
3 → 4
|
3383
|
1
|
617
|
1.000
|
4100
|
|
Scenario 2 Prevalence 10%:
|
1-test
|
2
|
980
|
90
|
20
|
0.916
| |
|
2-test
|
2 → 5
|
960
|
2
|
40
|
0.998
|
1070
|
|
1-test
|
3
|
995
|
180
|
5
|
0.847
| |
|
2-test
|
3 → 4
|
846
|
2
|
154
|
0.998
|
1175
|
|
Scenario 3 Prevalence 2%:
|
1-test
|
2
|
196
|
98
|
4
|
0.667
| |
|
2-test
|
2 → 5
|
192
|
2
|
8
|
0.990
|
294
|
|
1-test
|
3
|
199
|
196
|
1
|
0.504
| |
|
2-test
|
3 → 4
|
169
|
2
|
31
|
0.989
|
395
|
|
Scenario 4 Prevalence 0.4%
|
1-test
|
2
|
39
|
100
|
1
|
0.282
| |
|
2-test
|
2 → 5
|
38
|
2
|
2
|
0.951
|
139
|
|
1-test
|
3
|
40
|
199
|
0
|
0.167
| |
|
2-test
|
3 → 4
|
34
|
2
|
6
|
0.944
|
239
|
|
Test Kit Performance Characteristics:
|
|
Test Kits
|
Sensitivity
|
Specificity
| |
Test Kits
|
Sensitivity
|
Specificity
| |
|
2
|
98.0%
|
99.0%
| |
4
|
85.0%
|
99.0%
| |
|
3
|
99.5%
|
98.0%
| |
5
|
98.0%
|
98.0%
| |
|
Notes on Two-Test Strategies:
|
|
Assay B performance is considered independent of Assay A
| |
|
Outcome of 2-test strategy: A + B+ = pos and A-, A + B- = neg (Fig. 2)
| |
|
2-test strategies overall performance:
|
Assay A
|
Assay B
|
Sensitivity
|
Specificity
|
| | | | |
2
|
5
|
96.04%
|
99.98%
|
| | | | |
3
|
4
|
84.58%
|
99.98%
|
