Traditional Chinese Medicine or Low-dose Dexamethasone in COVID-19 Pneumonia

Inclusion Criteria: * Clinical diagnosis of COVID-19 pneumonia； * 3 to 8 weeks after the onset of the first symptoms of COVID-19 infection; * Modified Medical Research Council (mMRC) score ⩾2 or hypoxemia; * Imaging severity assessment of pneumonia: CT severity scores (CTSS):≥5； * Signed the informed consent. Exclusion Criteria: * Participants still admitted to intensive care unit at the time of enrollment; * Known prior structural lung disease, including pulmonary fibrosis, severe COPD, severe bronchiectasis, and lung destruction; * Taking glucocorticoids or immunosuppressants because of other chronic diseases; * Contraindications of glucocorticoid; * Heart failure(NYHA III or IV); * Participants with renal replacement therapy; * Psychiatric disorders or cognitive impairments; * The expected survival time is less than six months due to diseases other than COVID-19 pneumonia.