TABLE 2.

Comparison of IDI-MRSA assay, GenoType MRSA Direct, and selective MRSA agars in the detection of MRSA with all swabs (nasal, groin, and axilla)a

TestNo. of positive samplesbNo. of negative samplesbNo. of inhibited samplesSensitivity (%)Specificity (%)PPV (%)NPV (%)
Molecular detection tests
    IDI-MRSA75127390969394
    GenoType MRSA Direct59137969969282
Selective agars at 24 h
    MRSA ID5814771989584
    MRSASelect5015564958981
    CHROMagar MRSA5614963999881
Selective agars at 48 h
    MRSA ID1238282535283
    MRSASelect9810769746279
    CHROMagar MRSA8711871675679
  • a PPV, positive predictive value; NPV, negative predictive value.

  • b True positive (n = 78) and true negative (n = 127) samples, defined as described in the text.