Figure 1.

Characteristics of study population in different grades. (A) The distribution of males and females by grade. (B) Age distribution of patients in different grades. (C) Distribution of classical clinical symptoms of Russell’s viper bite in each category. (D) Distribution of elapsed time (hours) from bite to antivenom administration in different categories. This study only included patients who arrived at the hospital within 8 h following the bite. Multinomial logistic regression models were used to test whether gender, age, clinical symptoms, and time to antivenom were predictors of grade. The numbers shown on figure panels indicate the percentage in respective categories.