| Acute (≤8 weeks) | Chronic (>8 weeks) |
| Diseases of the lower airways | Diseases of the lower airways and lung parenchyma |
| Asthma | |
| Aspiration (commonly children aged 1–3 yrs) | Chronic (nonobstructive) bronchitis and COPD |
| Inhalation intoxication (accidents and fire) | Asthma and other eosinophilic diseases |
| Post-infectious cough | Lung tumours |
| Infectious diseases | |
| Diseases of the lungs and pleura | DPLD (systemic diseases with diffuse lung involvement) |
| Pneumonia | |
| Pleurisy | Aspiration and RADS |
| Pulmonary embolism | Bronchiectasis and cystic fibrosis |
| Pneumothorax | Bronchomalacia |
| Rare, localised disease of the tracheobronchial tree |
COPD: chronic obstructive pulmonary disease; DPLD: diffuse parencymatous lung diseases; RADS: reactive airways dysfunction syndrome.