Table 2.
Sensitivity, specificity, and kappa value of SGS (n = 171) a
| BALF culture n (%) |
SGS n (%) |
Sensitivity %(95% CI) b |
Specificity %(95% CI)b |
Kappa value (95% CI) b |
|
|---|---|---|---|---|---|
| G+cocci | 28(16.37) | 74(43.27) | 87(65–97) | - | - |
| G-cocci | 9(5.26) | 17(9.94) | 56(23–85) | - | - |
| G+bacilli | 0 | 2(1.17) | - | - | - |
| G-bacilli | 17(9.94) | 13(7.60) | 50(23–78) | - | - |
| Mixed bacteria | 0 | 41(23.98) | - | - | - |
| Negative | 117(68.42) | 24(14.04) | - | - | - |
| Total | 171(100.00) | 171(100.00) | 70(55–83) | 23(15–34) | 0.199(0.107–0.292) |
SGS Sputum Gram stain, BALF Bronchoalveolar lavage fluid, CI Confidence interval, G+cocci Gram-positive cocci, G-cocci Gram-negative cocci, G+bacilli Gram-positive bacilli, G-bacilli Gram-negative bacilli
a Reference standard is bronchoalveolar lavage fluid culture
b Calculation was performed after mixed bacteria cases were excluded