Table 2.

Results of the DML Staph assay in the strain study, comparing the results with three third-generation latex assays. The gold standard determination (coagulase-negative staphylococci [CNS], methicillin-susceptible S. aureus [MSSA], methicillin-resistantS. aureus [MRSA]) of the non-interpretable strains is shown; these strains were excluded from further statistical analysis. The sensitivity, specificity, positive and negative predictive values (PPV and NPV, respectively) are shown. The p-value was calculated two-tailed using McNemar’s test for any of the third-generation assays versus the DML Staph assay

N = 793	DML Staph			Slidex Staph Plus			Staphaurex Plus			Pastorex Staph-Plus
Non-interpretable strains (%)	0 (0)			3× CNS; 2× MRSA (0.6)			3× MRSA (0.4)			10× CNS; 2× MRSA (1.5)
n = 782	All	MSSA	MRSA	All	MSSA	MRSA	All	MSSA	MRSA	All	MSSA	MRSA
Sensitivity (%)	99.2	99.6	98.8	98.1	100	96.1	95.2	99.2	91.3	98.2	99.2	97.3
Specificity (%)	100	100	100	100	100	100	100	100	100	98.8	98.8	98.8
PPV (%)	100	100	100	100	100	100	100	100	100	99.4	98.8	98.8
NPV (%)	98.4	99.6	98.8	96.1	100	96.1	91.3	99.2	91.9	96.5	99.2	97.2
p-value	–	–	–	0.1489	0.2482	0.1489	0.0001	0.4795	0.0001	0.7728	0.7518	0.4492