Synthesis of results
A systematic review showed that 610 patients (42.8%) with COVID-19 pneumonia were female. Fever (89.2%) and cough (67.2%) were the most common symptoms, followed by fatigue (43.6%), phlegm (28.6%), and shortness/difficulty of breathing (21.7%). The less common symptoms were dizziness (0.9%), hemoptysis (0.8%), abdominal pain (0.8%), and conjunctiva congestion/conjunctivitis (0.7%). 1,377 cases were divided into groups of severe (1,110) and non-severe COVID-19 pneumonia (267). Stratified chi-square test showed that there was no significant difference in gender between the two groups (p>0.05), and the median age of severe patients was slightly older (details in Table 2). Dyspnea in patients of severe group was significantly more common than that in non-severe group (42.7% vs.16.3%, p<0.0001). The incidence of fever and diarrhea were also significantly higher in severe group (p=0.0374 and 0.0267 respectively). Although conjunctival congestion/conjunctivitis (p=0.0176), hemoptysis (p=0.0344), anorexia (p=0.0008), dizziness (p=0.0023) and abdominal pain (p=0.0015) all appeared to be much more common in severe patients, as the dates of these symptoms were only reported in one or two literatures, the inter-group comparisons of these symptoms should be treated with caution. (See Table 1 and 2 )