Table 2.
Summary of performance metrics for isothermal amplification methods. The mean value for each method/metric/unit combination was calculated. The number of studies in which the metric was measured is included parenthetically (). Where possible, units and values were converted to allow direct comparison, e.g. values originally reported as fg/μL were converted to ng/μL. All units representing nucleic acids (GC, ng) are normalized per μL of template volume. A detailed compilation of characteristics for each study is provided in supplemental Table S1.
| Method | Limit of Detection Unit |
Mean Limit of Detectionb |
Sensitivity | Specificity |
|---|---|---|---|---|
| HDA | GCa/μL | 6.46 x 100 (2) | 99% (2) | 100% (?) |
| LAMP | GC/μL | 8.78 x 101 (4) | 94.4% | 99.8% |
| GC/reactionc | 2.24 x 101 (4) | |||
| ng/μL | 2.19 x 10−3 (26) | |||
| cells/μL | 5.45 x 100 (7) | |||
| CFU/μLd | 1.15 x 100 (7) | |||
| CFU/μg fecese | 2.43 x 10−3 (2) | |||
| LF-RPA | GC/μL | 2.60 x 101 (1) | 93.3% | 100% |
| NASBA | GC/μL | 2.02 x 102 (2) | 100% | 95.5% |
| cells/μL | 1.97 x 100 (3) | |||
| CFU/μL | 8.34 x 101 (6) | |||
| PFU/μL | 2.00 x 100 (1) | |||
| ng/μg tissue | 6.67 x 10−8 (1) | |||
| RCA | GC/μL | 1.00 x 101 (1) | 100% | 99.8% |
| cells/μL | 1.00 x 100 (2) | |||
| ng/μL | 7.03 x 10−6 (4) | |||
| RPA | GC/μL | 2.43 x 101 (2) | 98.7% | 100% |
| cells/μL | 2.02 x 10−2 (5) | |||
| ng/μL | 2.51 x 100 (5) |
GC gene copies
Number of publications where units were comparable or could be readily converted for comparison.
Values normalized per reaction in the publication were converted to per μL template volume unless template volume was not provided.
Converted to CFU/μL from CFU/mL for comparison
Converted to CFU/μg feces from CFU/g feces for ease of comparison