Difficult breathing analysis
Difficult breathing was less common in the patients of COVID‐19 and influenza. The prevalence of difficult breathing assessed in 4 articles comprising 27 patients and is reported to range from 6.87–100%. Due to the heterogeneity in the results of the primary studies, the random-effects model was employed. Combined analysis of these articles revealed that difficult breathing occurred in (9.3% [95% CI 3.7–21.5, p < 0.010]). Figure 5 (E).