Table 3. Weighted meta-regression of the effects of study settings, methods, and methodological quality on diagnostic accuracy of interferon-γ release assays.
| Covariate | Number of studies | Co-efficient | RDOR | P-value |
|---|---|---|---|---|
| Body Fluid | ||||
| QUADAS score | ||||
| ≥11 | 8 | –0.46 | 0.63 (0.14–2.92) | 0.537 |
| <11 | 13 | |||
| Setting | ||||
| High TB burden | 8 | –0.41 | 0.67 (0.14–3.13) | 0.591 |
| Low TB burden | 15 | |||
| Method | ||||
| ELISPOT | 15 | –0.44 | 0.64(0.13–3.09) | 0.437 |
| ELISA | 8 | |||
| Disease | ||||
| Pleurisy | 14 | –0.43 | 0.65 (0.07–6.49) | 0.701 |
| Peritonitis | 2 | 0.54 | 1.72 (0.05–57.87) | 0.751 |
| Meningitis | 4 | –0.54 | 0.58 (0.03–9.75) | 0.693 |
| Pericarditis | 1 | dropped | dropped | |
| Peripheral Blood | ||||
| QUADAS score | ||||
| ≥11 | 8 | 0.67 | 1.95 (0.91–4.18) | 0.082 |
| <11 | 11 | |||
| Settings | ||||
| High TB burden | 9 | –0.23 | 0.80 (0.38–1.65) | 0.519 |
| Low TB burden | 12 | |||
| Method | ||||
| ELISPOT | 13 | –0.32 | 0.73 (0.34–1.58) | 0.402 |
| ELISA | 8 | |||
| Disease | ||||
| Pleurisy | 12 | –1.36 | 0.26 (0.05–1.32) | 0.098 |
| Peritonitis | 2 | dropped | dropped | |
| Meningitis | 4 | –1.99 | 0.14 (0.02–0.79) | 0.029 |
| Mixed* | 3 | –1.61 | 0.20 (0.04–1.12) | 0.066 |
*Studies contained different extrapulmonary tuberculosis types, including pleurisy, peritonitis, meningitis, and pericarditis.