Table 3.

Results of the DML Staph assay versus the Slidex Staph Plus assay in the daily practice study. The gold standard determination(CNS, MSSA, MRSA) of the non-interpretable strains is shown; these strains were excluded from further statistical analysis. The sensitivity,specificity, PPV and NPV are shown. The p-value was calculated two-tailed using McNemar’s test for the Slidex Staph Plus assay versus the DML Staph assay

N = 1,865	DML Staph			Slidex Staph Plus
Non-interpretable strains (%)	17× CNS; 1× MSSA; 2× MRSA (1.1)			34× CNS; 1× MSSA; 1× MRSA (1.9)
n = 1,820	All	MSSA	MRSA	All	MSSA	MRSA
Sensitivity (%)	99.4	99.9	96.2	99.7	100	97.7
Specificity (%)	95.7	95.7	95.7	98.3	98.3	98.3
PPV (%)	96.4	95.9	78.1	98.6	98.4	90.3
NPV (%)	99.3	99.9	99.4	99.6	100	99.6
p-value	–	–	–	0.0005	0.0000	0.0002