Fig. 3

Funnel plots. a Headache, b myalgia, c smell impairment, d taste dysfunction, e dizziness, f seizure, g stroke, h encephalopathy, i intracerebral haemorrhage, j alteration of consciousness, k altered mental status, l vision impairment, m Guillan-Barré Syndrome (GBS) and n encephalitis. After the bias test, the visual symmetry of the funnel plot and Egger's test showed that the publication of myalgia, taste dysfunction, encephalopathy and vision impairment was unbiased