Table 1.
The Performance Characteristics of Test Methods
| Tests Performed | Positive Patients/Number Tested (%) | Number (Percentage) Detected by Method (%) | Statistical Significance (Chi-Square) | Sensitivity, % | Negative Predictive Value, % |
|---|---|---|---|---|---|
| Comparison of morphologic methods | |||||
| Toluidine blue and cytology | 7/231 (3.0) | TB: 6/7 (85.7) Cy: 3/7 (42.9) |
Not performed a | TB: 85.7 Cy: 42.9 |
TB: 99.6 Cy: 98.2 |
| Toluidine blue and surgical pathology | 7/1046 (0.67) | TB: 5/7 (71.4) SP: 5/7 (71.4) |
P = 1.00 | TB: 71.4 SP: 71.4 |
TB: 99.8 SP: 99.8 |
| Toluidine blue, cytology, and surgical pathology | 7/114 (6.1) | Detected by: All 3 methods: 1/7 (14.3) TB alone: 2/7 (28.6) SP alone: 1/7 (14.3) TB and SP: 2/7 (28.6) SP and Cy: 1/7 (14.3) |
Not performeda | TB: 71.4 Cy: 28.6 SP: 71.4 |
TB: 98.2 Cy: 95.5 SP: 98.2 |
| Comparison of PCR with cytology and surgical pathology | |||||
| PCR and cytology | 21/282 (7.4) | PCR: 21/21 (100) Cy: 5/21 (23.8) |
P < .001 | PCR: 100 Cy: 23.8 |
PCR: 100 Cy: 94.2 |
| PCR and surgical pathology | 4/874 (0.46) | PCR: 4/4 (100) SP: 3/4 (75) |
Not performeda | PCR: 100 SP: 75 |
PCR: 100 SP:99.9 |
| PCR, cytology, and surgical pathology | 3/123 (2.4) | Detected by: PCR and SP: 2/3 (66.6) PCR alone: 1/3 (33.3) |
Not performeda | PCR: 100 SP: 66.6 Cy: 0.0 |
PCR: 100 SP: 99.2 Cy: 0.0 |
Abbreviations: Cy, cytology; NPV, negative predictive value; PCR, Pneumocystis polymerase chain reaction–based assay; SP, surgical pathology; TB, toluidine blue staining.
aChi-square tests were not performed when cell values were less than 5.