Table 1.

Characteristics, clinical specimen distribution, and culture positive rate of SBA and SAA groups

	SBA group N = 19,868	SAA group N = 7924	P value
Demographic
Age in yr, medians (IQR)	60 (47–70)	61(49–72)	< 0.001
male (%)	12,477 (62.8%)	4938 (62.3%)	0.443
Department distribution
Intensive Care Unit	1582 (8.0%)	499 (6.3%)	< 0.001
Surgery departments	8760 (44.1%)	3873 (48.9%)	< 0.001
Internal departments	8849 (44.5%)	3114 (39.3%)	< 0.001
Others	677 (3.4%)	428 (5.5%)	< 0.001
Distribution of Clinical specimens
Respiratory specimens a	7351 (37.0%)	3162 (39.9%)	< 0.001
Blood	4229 (21.3%)	1196 (15.1%)	< 0.001
Body fluid specimens b	1495 (7.5%)	1131 (14.3%)	< 0.001
Urine	4311 (21.7%)	947 (12.0%)	< 0.001
Stool	403 (2.0%)	297 (3.7%)	< 0.001
Other specimens c	2079 (10.5%)	1191 (15.0%)	< 0.001
Culture positive rate
Culture positive, n (%)	5650 (28.4%)	2014 (25.4%)	< 0.001
Polymicrobial result, n (%)d	864 (15.3%)	320 (15.9%)	0.525

Abbreviations: SBA specimen taken before antibiotic therapy, SAA specimen taken after antibiotic therapy

^a including sputum, throat swab, tracheal aspirate, protected bronchial brush, and bronchoalveolar lavage

^b including cerebrospinal fluid, pleural fluid, ascites, bile, puncture fluid, and pericardial effusion

^c including intravascular catheter tip, various secretions, peritoneal dialysate, pus, drainage fluid, biopsy tissue and other specimens

^d Polymicrobial result was defined as more than one pathogen cultured from the same specimen