TABLE 2.

QTD PCR assay results with and without cutoff value of 10 MSG copies/tube applied^a

Specimen and assay	No. of PCR-positive specimens/total no. of PCP samples	No. of PCR-positive specimens/total no. of non-PCP samples
Lower respiratory tract (n = 49)
QTD PCR	19/19	10/30
QTD PCR > 10 copies	16/19	2/30
Conventional MSG PCR	18/19	11/30
Oral wash (n = 49)
QTD PCR	17/18	3/31
QTD PCR > 10 copies	15/18	0/31
Conventional MSG PCR	18/18	6/31

^aConventional qualitative MSG PCR assay results are given for reference. Concordance between the QTD PCR assay without cutoff and the conventional qualitative MSG PCR assay was 94% (92 of 98 samples).