Table 1.

Eligibility criteria

Inclusion criteria	Exclusion criteria
Hospitalised patients with AECOPD*	Fever, axillary temperature ≥38°C
≥40 years of age	Pneumonia identified by X-ray or CT of the chest
Able to understand and communicate to ensure the completion of the trial	Severe respiratory failure requiring admittance to ICU Concurrent infection at another site (eg, urinary tract infection)
Voluntary participation and provide written informed consent	Immunosuppression secondary to chemotherapy, AIDS or malignant tumour of blood system
	Comorbidities requiring corticosteroids (at least prednisone 30 mg/day or equivalent for more than 30 days)
	Invasive mechanical ventilation
	Patients with malignant tumours receiving chemotherapy or radiotherapy
	Pregnancy
	Participation in another clinical trial
	Previously enrolment into the study
	Refuse to attend

*The diagnostic criteria for AECOPD are based on the recommendation in Global Initiative for Chronic Obstructive Pulmonary Disease guideline.⁴

AECOPD, acute exacerbation of chronic obstructive pulmonary disease; AIDS, acquired immunodeficiency syndrome; CT, computer tomography; ICU, intensive care unit.