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Table 1 Prevalence of infection and sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) as well as Cohen’s Kappa index (Kappa) based on data obtained using buffy coat method (BCM) and microscopic examination (ME) of blood films

From: The buffy coat method: a tool for detection of blood parasites without staining procedures

Parasite Overall prevalencea BCMa MEa Sensitivityb Specificityb PPVb NPVb Kappac
Haemoproteus 135 (39.1) 125 (92.6) 113 (83.7) 91.2 (85.9–96.4) 90.5 (86.8–94.3) 82.4 (75.7–89.1) 95.5 (92.7–98.2) 0.80 (0.73–0.86)
Trypanosoma 91 (26.4) 91 (100) 0 (0) d 73.6 (69.0–78.3) d 100 (100) d
Plasmodium 18 (5.2) 0 (0) 18 (100) d 100 (100) d 94.8 (92.4–97.1) d
Lankesterella 13 (3.8) 10 (76.9) 7 (53.9) 57.1 (20.5–93.8) 98.0 (97.0–100) 40.0 (9.6–70.4) 99.1 (98.1–100) 0.46 (0.16–0.76)
Leucocytozoon 6 (1.7) 2 (33.3) 5 (83.3) 20.0 (0–55.1) 99.7 (99.1–100) 50.0 (0–100) 98.8 (97.7–100) 0.28 (0–0.72)
Microfilaria 6 (1.7) 6 (100) 1 (16.7) 100 (100) 98.6 (97.3–99.8) 16.7 (0–46.5) 100 (100) 0.28 (0–0.72)
  1. aNumber of positive samples followed by infection prevalence (in %) in parentheses
  2. bPercentage, followed by the 95% confidence interval in parentheses
  3. cKappa index followed by the 95% confidence interval (in parentheses)
  4. dCalculation not possible because the parasites were detected only by ME
  5. Note: ME was considered as the gold standard method