Table 2. Results of the clinical and analytical variables.
| Clinical variables | BPE | MPE |
| Gender (male/female) a | 138/60 (69.7/30.3) | 59/50 (54.1/45.9) |
| Age (years)b | 65.5 (51–77.25) | 70 (60–80.5) |
| Previous cancera | 35 (17.7) | 34 (31.2) |
| Smoker a | 106 (53.5) | 57 (52.3) |
| Dyspnoea a | 123 (62.1) | 89 (81.7) |
| Chest pain a | 97 (49) | 39 (35.8) |
| Cough a | 79 (30.9) | 35 (32.1) |
| Constitutional syndrome a | 28 (14.1) | 46 (42.2) |
| Haemoptysis a | 7 (3.5) | 5 (4.6) |
| Fever a | 72 (36.4) | 8 (7.3) |
| Massive effusion a, c | 17 (8.6) | 30 (27.5) |
| Analytical variables b | BPE | MPE |
| LDH (U/L) | 438 (283–998) | 522 (341–832) |
| Protein (g/dL) | 4.59 (3.9–5.03) | 4.4 (3.78–4.87) |
| pH | 7.39 (7.29–7.44) | 7.40 (7.32–7.45) |
| ADA (U/L) | 24 (19.4–40.62) | 20 (14.8–25.85) |
| Glucose (mg/dL) | 99.5 (76–127) | 105 (90–126) |
| Polymorphonuclear leukocytes (%) | 21 (5–59) | 9 (2–20) |
| Mononuclear leukocytes (%) | 70 (31.25–90) | 82 (50.5–94.25) |
BPE = benign pleural effusion; MPE = malignant pleural effusion; constitutional syndrome includes at least one of the following variables: asthenia, anorexia, and/or weight loss; LDH = lactate dehydrogenase; ADA = adenosine deaminase.
a Data are presented as frequencies and percentages
b Data are presented as medians and interquartile ranges (IQRs)
c Radiological effusion features: pleural effusion causing opacification of an entire hemithorax or when the fluid reaches the aortic arch.