Table 1.
Summary of Differences in Sensitivity and Specificity Between the QuantiFERON-TB Gold Plus and the QFT-GIT or the T-SPOT.TB Assays
| Comparator/Outcome | Analysis | Studies, No. | Subjects Tested, No. | Correctly Classified (QFT-Plus), No. | Correctly Classified (Comparator), No. | Pooled Estimate QFT-Plus, % (95% CI); I2 | Pooled Estimate Comparator, % (95% CI); I2 | Difference in Sensitivity or Specificitya (QFT-Plus – Comparator), % Points (95% CI); I2 | Certainty of the Evidence (GRADE) |
|---|---|---|---|---|---|---|---|---|---|
| QFT-GIT as comparator | |||||||||
| Sensitivity | Paired comparisons (published studies)b | 5 | 505 | 432 | 431 | 90.1 (76.6–96.2); 90% | 89.4 (76.7–95.6); 92% | −0.1 (−2.8 to 2.6); 11% | Moderatec ⊕⊕⊕○ |
| Paired comparisons (all studies) | 7 | 972 | 861 | 864 | 90.8 (82.4–95.4); 90% | 90.6 (82.4–95.2); 92% | −0.5 (−1.9 to 0.9); 10% | ||
| Parallel comparisons (published studies) | 9 | 903 | 792 | 787 | 90.3 (84.2–94.2); 86% | 89.3 (83.1–93.4); 88% | 0.5 (−1.6 to 2.6); 12% | ||
| Parallel comparisons (All studies) | 12 | 1397 | 1244 | 1244 | 90.4 (85.8–93.6); 84% | 90 (85.4–93.3); 87% | 0.0 (−1.5 to 1.5); 11% | ||
| Specificity | Paired comparisons (published studies)b | 1 | 211 | 207 | 209 | 98.1 (95.2–99.5); NA | 99.1 (96.6–99.9); NA | −0.9 (−3.5 to 1.1); NA | Moderatec ⊕⊕⊕○ |
| Paired comparisons (all studies) | 6 | 1137 | 1101 | 1113 | 97.1 (92.6–98.9); 75% | 98.6 (94.4–99.7); 72% | −1.0 (−2.0 to 0.1); 26% | ||
| Parallel comparisons (published studies) | 3 | 529 | 518 | 523 | 97.9 (96.3–98.8); 0% | 98.9 (97.5–99.5); 0% | −0.9 (−1.0 to −0.9); 0% | ||
| Parallel comparisons (all studies) | 9 | 1505 | 1461 | 1476 | 97.3 (94.9–98.6); 65% | 98.5 (96.5–99.4); 62% | −0.9 (−1.5 to −0.3); 11% | ||
| T-SPOT.TB as comparator | |||||||||
| Sensitivity | Paired comparisonsb (published studies) | 1 | 99 | 98 | 96 | 99.0 (94.5–100); NA | 97.0 (91.4–99.4); NA | 2.0 (−2.4 to 7.4); NA | Lowc,e ⊕⊕○○ |
| Paired comparisons (all studies)d |
1 | 99 | 98 | 96 | 99.0 (94.5–100); NA | 97.0 (91.4–99.4); NA | 2.0 (−2.4 to 7.4); NA | ||
| Parallel comparisons (published studies) | 3 | 252 | 238 | 223 | 95.1 (87.5–98.2); 63% | 90.8 (75.4–97.0); 89% | 5.8 (−22.2 to 33.8); 84% | ||
| Parallel comparisons (all studies)d | 3 | 252 | 238 | 223 | 95.1 (87.5–98.2); 63% | 90.8 (75.4–97.0); 89% | 5.8 (−22.2 to 33.8); 84% | ||
| Specificity | Paired comparisonsb (published studies) | 0 | … | … | … | … | … | … | Lowc,e ⊕⊕○○ |
| Paired comparisons (all studies) | 1 | 50 | 49 | 50 | 98.0 (89.4–99.9); NA | 99.0 (92.9–100); NA | −2.0 (−10.5 to 5.3); NA | ||
| Parallel comparisons (published studies) | 1 | 106 | 104 | 104 | 98.1 (93.4–99.8); NA | 98.1 (93.4–99.8); NA | 0.0 (−4.9 to 4.9); NA | ||
| Parallel comparisons (all studies) | 2 | 156 | 153 | 154 | 98.1 (94.2–99.4); 0% | 98.7 (95–99.7); 0% | −0.6 (−12.0 to 10.9); 1% | ||
A summary of each analysis, including information from individual studies, is shown in Supplementary Material Part B, Supplementary Tables 12–15 (sensitivity) and Supplementary Tables 16–19 (specificity). Forest plots of pooled sensitivities and specificities are shown in in Supplementary Material Part B, Supplementary Figures 10–12 and 13–14, respectively. For a summary of the risk of bias assessment, please refer to Supplementary Figures 3–6. In line with the GRADE approach, the certainty of evidence (CoE) is categorized into four levels: very low (⊕○○○), low (⊕⊕○○), moderate (⊕⊕⊕○), and high (⊕⊕⊕⊕).
Abbreviations: CI, confidence interval; GRADE, Grading of Recommendations Assessment, Development and Evaluation; NA, not available.
Pooled differences in sensitivity or specificity do not match exactly to the differences in the pooled sensitivities or specificities since they correspond to different meta-analytical approaches.
Primary analysis.
Downgraded because most studies were considered at unclear risk of bias.
No unpublished studies were included in this analysis; results are repeated from the analysis including only published studies.
Downgraded because CIs are very wide and hence consistent with both an appreciable gain and appreciable loss in diagnostic accuracy.