TABLE 1.

Summary of in-house PCR methods for detection of C. pneumoniae

Variable	Laboratory site
	A	B	C	D	E
PCR format	Single	Nested	Single	Nested	Nested
Target gene	16S rRNA	ompA	Cloned PstI	ompA	ompA
Primers	CPNA-CPNB	CP1-CP2, CPC-CPD	HL1-HR1	CP1-CP2, CPC-CPD	CP1-CP2, CPC-CPD
Amplicon size (bp)	463	207	474	207	207
No. of replicates tested	1	3	4	2	1 or 2
Criterion for positivity	1/1	1/3	1/4	1/2	1/1 or 1/2
Size of PCR mixture (μl)	50	50	50	50	100
Vol of original specimen used in PCR (μl)	15	10	0.1, 0.5, 1, 5	10	10
Vol of amplicon transferred in nested PCR (μl)	N/Aa	2.5b	N/A	5c	10d
Detection method	AGEe	AGE	AGE and hybridization	AGE	AGE
Reference	7	23	5	23	23

^aN/A, not applicable.

^bThe amplicon was diluted 1:10, and 2.5 μl of the dilution was added to 25 μl of the round 2 reaction mixture.

^cThe amplicon was diluted 1:2, and 5 μl of the dilution was added to 50 μl of the round 2 reaction mixture.

^dTen microliters of undiluted amplicon was added to 100 μl of the round 2 reaction mixture.

^eAGE, agarose gel electrophoresis.