Table 2.

Reference Standard Tests^a

Target Pathogen	RS Group per Pathogen	Culture							Inoculation	Antigen Test			PCR		Frequency of Cohorts [Reference]
		Sputum	Tracheal Aspirates	Bronchial Aspirates	Pleural Effusion	BAL Fluid	Blood	Urine	Sputum	Sputum	Blood	Urine	Sputum	Specimen From the Lesion
Studies that reported the data on any-quality specimens
SP	1	1	0	0	0	0	0	0	0	0	0	0	0	0	5 [17, 21, 28, 36]
	2	1	0	0	0	0	1	0	0	0	0	0	0	0	2 [26, 31]
	3	1	0	0	0	0	1	0	0	0	0	1	0	0	1 [35]b
	4	1	0	0	0	0	1	1	0	1	1	1	0	0	1 [22]
	5	1	0	0	1	0	1	0	0	0	0	0	0	1	1 [27]
	6	1	1	1	0	0	1	0	1	0	0	0	0	0	1 [18]
HI	1	1	0	0	0	0	0	0	0	0	0	0	0	0	1 [28]
	2	1	0	0	0	0	1	0	0	0	0	0	0	0	1 [35]
	3	1	0	0	1	0	1	0	0	0	0	0	0	0	1 [27]
Studies that reported the data on good-quality specimens only
SP	1	0	0	0	0	0	0	0	0	0	0	0	1	0	1 [37]
	2	0	0	0	1	0	1	0	0	0	0	0	0	0	1 [29]c
	3	1	0	0	0	0	0	0	0	0	0	0	0	0	2 [33, 35]b
	4	1	0	0	0	0	0	0	1	0	0	0	0	0	1 [23]
	5	1	0	0	0	0	0	0	1	1	0	0	0	0	1 [19]
	6	1	0	0	1	0	1	0	0	0	0	0	0	0	1 [25]
	7	1	0	0	1	0	1	0	0	0	0	0	0	1	1 [27]
	8	1	0	0	1	1	1	0	0	0	0	1	0	0	1 [38]
	9	1	1	1	0	0	1	0	0	0	0	0	0	0	1 [32]
	10	1	1	1	0	1	1	0	0	0	0	0	0	0	1 [30]
HI	1	0	0	0	0	0	0	0	0	0	0	0	1	0	1 [37]
	2	1	0	0	0	0	0	0	0	0	0	0	0	0	1 [33]
	3	1	0	0	0	0	1	0	0	0	0	0	0	0	1 [35]
	4	1	0	0	1	0	1	0	0	0	0	0	0	0	2 [25, 27]
	5	1	0	0	1	1	1	0	0	0	0	0	0	0	1 [38]
KP	1	1	0	0	1	1	1	0	0	0	0	0	0	0	1 [38]
MC	1	1	0	0	1	1	1	0	0	0	0	0	0	0	1 [38]
PA	1	1	0	0	1	1	1	0	0	0	0	0	0	0	1 [38]
SA	1	1	0	0	1	1	1	0	0	0	0	0	0	0	1 [38]

Abbreviations: BAL, bronchoalveolar lavage; HI, Haemophilus influenzae; KP, Klebsiella pneumoniae; MC, Moraxella catarrhalis; PA, Pseudomonas aeruginosa; PCR, polymerase chain reaction; RS, reference standard; SA, Staphylococcus aureus; SP, Streptococcus pneumoniae.

^aTests adopted in each composite RS group (shown in a row) are coded as “1” and those not adopted as “0.”

^bData on good-quality specimens for detecting SP were extractable for RS based on sputum culture only.

^cData were based on the composite RS excluding sputum Gram stain.