Table 1. Characteristics of patients.

	Total (n = 79)	Success (n = 64)	Failure (n = 15)	p
Demographical and Clinical characteristics
Median age, years (IQR)	54 (46–71)	56 (45.5–71)	53 (47–72)		0.803
Male gender, n (%)	57 (72%)	45 (70%)	12 (80%)		0.539
Community-acquired infection, n (%)	72 (91%)	59 (92%)	13 (87%)		0.612
Delay symptoms-admission, days (IQR)	10 (5–22)	10 (4.5–21)	8 (5–25)		0.837
Smoker, n (%)	49 (62%)	39 (61%)	10 (67%)		0.774
COPD, n (%)	7 (9%)	6 (9%)	1 (7%)		1.000
Heart disease, n (%)	11 (14%)	9 (14%)	2 (13%)		1.000
Diabetes mellitus, n (%)	8 (10%)	5 (8%)	3 (20%)		0.171
Immunodepression, n (%)	6 (8%)	4 (6%)	2 (13%)		0.319
Alcohol abuse, n (%)	25 (32%)	19 (30%)	6 (40%)		0.540
Cancer, n (%)	13 (16.5%)	10 (16%)	3 (20%)		0.704
Chronic liver disease, n (%)	9 (11%)	5 (8%)	4 (27%)		0.061
Neurological impairment, n (%)	25 (32%)	19 (30%)	6 (40%)		0.540
Non-steroid anti-inflammatory drugs, n (%)	15 (19%)	14 (22%)	1 (7%)		0.279
Corticosteroids >3 weeks, n (%)	9 (11%)	8 (12.5%)	1 (7%)		1.000
Antibiotics initiated before thoracentesis, n (%)	37 (47%)	32 (50%)	5 (33%)		0.268
Radiological data
Right side location, n (%)	46 (58%)	36 (56%)	10 (67%)		0.567
Large effusion (> ½ thorax), n (%)	43 (55%)	33 (52%)	10 (67%)		0.509
Bilateral effusion, n (%)	5 (6%)	5 (8%)	0 (0%)		0.576
Mediastinal shift, n (%)	17 (22%)	10 (16%)	7 (47%)		0.016
Loculations, n (%)	47 (66%)	38 (68%)	9 (60%)		0.557
Index of diseases severity
Respiratory failure, n (%)	12 (15%)	9 (14%)	3 (20%)		0.689
Severe sepsis, n (%)	4 (5%)	3 (5%)	1 (7%)		0.577
Impaired consciousness-Confusion	8 (10%)	6 (9%)	2 (13%)		0.643
Urea, mmol/L (IQR)	5.4 (3.4–8.1)	5.3 (3.4–8.0)	5.9 (3.6–8.2)		0.762
Albumin, g/L (IQR)(†)	22.1 (20.0–24.0)	22.2 (21.7–24.5)	20.9 (19.0–23.0)		0.177

IQR: Interquartile range; COPD: chronic obstructive pulmonary disease.

Quantitative variables are indicated as median (IQR), qualitative variables are indicated as numbers (%). (†) Variables with >10% of missing data.