Prevalence of LTBI
|
0.30
|
0.1-0.4
|
[24, 39, 40]
|
TST return rate
|
0.90
|
0.65-0.95
|
[14, 27]
|
T-SPOT.TB sensitivity
|
0.95
|
0.83-0.97
|
[30, 41–43]
|
T-SPOT.TB specificity
|
1.00
|
0.92-0.99
|
[41, 43]
|
T-SPOT.TB positive result
|
0.285
| |
Calculated
|
T-SPOT.TB true positive (PPV)
|
1.000
| |
Calculated
|
T-SPOT.TB true negative (NPV)
|
0.979
| |
Calculated
|
T-SPOT.TB true positive (PPV) given a positive TST
|
1.000
| |
Calculated
|
T-SPOT.TB negative (NPV) given a positive TST
|
0.987
| |
Calculated
|
QFT-GIT sensitivity
|
0.89
|
0.85-0.95
|
[32, 44]
|
QFT-GIT specificity
|
0.95
|
0.90-0.97
|
[32, 44]
|
QFT-GIT positive result
|
0.302
| |
Calculated
|
QFT-GIT true positive (PPV)
|
0.884
| |
Calculated
|
QFT-GIT true negative (NPV)
|
0.953
| |
Calculated
|
QFT-GIT true positive (PPV) given a positive TST
|
0.930
| |
Calculated
|
QFT-GIT true negative (NPV) given a positive TST
|
0.971
| |
Calculated
|
TST sensitivity
|
0.85
|
0.69-0.95
|
[30, 41, 42, 45]
|
TST specificity
|
0.80
|
0.65-0.90
|
[20, 46]
|
TST positive result
|
0.395
| |
Calculated
|
TST true positive (PPV)
|
0.646
| |
Calculated
|
TST true negative (NPV)
|
0.926
| |
Calculated
|
Start INH treatment
|
0.80
|
0.55-0.95
|
[47]
|
Develop severe INH hepatitis
|
0.003
|
0.003-0.041
|
[47–50]
|
Death due to hepatitis
|
0.00002
|
0.00001-0.0001
|
[51, 52]
|
Efficacy of 3 months INH (LTBI fully cured)
|
0.21
|
0.1-0.3
|
[23, 24, 53]
|
LTBI not cured (with 3 months INH)
|
0.79
|
0.7-0.9
|
[23, 24, 53]
|
Efficacy of 6 months INH (LTBI fully cured)
|
0.65
|
0.5-0.93
|
[10, 17, 23, 49, 53, 54]
|
LTBI not cured (with 6 months INH)
|
0.35
|
0.07-0.5
|
[10, 17, 23, 49, 53]
|
Post exposure TB
|
0.025
|
0.01-0.05
|
[14, 55]
|
TB remains latent
|
0.975
|
0.95-0.99
|
[14, 55]
|
Cost (British Pounds; £s)
| | | |
T-SPOT.TB (kit, consumables and processing) + phlebotomy
|
55.00
|
45.00-100.00
|
Test cost from Royal Free Hospital, London; Phlebotomy cost from [56]
|
TST(cost of disposables, administration and reading)
|
16.14
|
8.07-32.28
|
[7, 18, 57]
|
QFT-GIT (kit, consumables and processing) + phlebotomy
|
45.00
|
35.00-80.00
|
Test cost from Royal Blackburn Hospital; Phlebotomy cost from [56]
|
Treatment for severe INH hepatotoxicity
|
629.12
|
314.56-1258.24
|
[18, 20, 56]
|
3 months INH treatment
|
484.38
|
242.19-968.76
|
Calculated from [7, 18]
|
6 months INH treatment
|
524.59
|
262.30-1049.18
|
[7, 18]
|
Treatment for active TB
|
7619.67
|
3809.84-15239.34
|
[18, 37]
|