Fifteen studies, evaluating 1,738 specimens, were included in thereview.
Of the 15 included studies, only two reported blinding of the researchers to the results of the reference standard and/or LiPA. No study prospectively enrolled consecutive patients. All studies had complete verification of LiPA results with a reference standard.
Inter-rater agreement for sensitivity and specificity was 80%.
Accuracy of LiPA in culture isolates (14 studies).
The sensitivity ranged from 82 to 100% and the specificity ranged from 92 to 100%. The AUC, derived from the summary ROC curve, was 0.99 (SE=0.0017) and the Q* index was 0.97 (SE=0.005).
Accuracy of LiPA in clinical specimens (4 studies).
The sensitivity ranged from 80 to 100%, while the specificity was 100% for all 4 studies. One study stated that 13 of the 60 samples tested were indeterminate because of failure at the polymerase chain reaction stage; these were excluded from the analysis.
Rifampicin resistance as a marker for multi-drug resistant TB (4 studies).
Four studies determined the number of RIF-resistant samples that were also isoniazid resistant (the criteria for multi-drug resistant TB). On average, 91% of RIF-resistant samples were also isoniazid resistant.