Note: A patient is tested positive in sIgE if the sIgE level ≥ 0.35 kUA/L. These sIgE positive patients are categorized further into six classes based on the absolute sIgE level: class 1 (0.35 ~ 0.70 kUA/L), class 2 (0.70 ~ 3.50 kUA/L), class 3 (3.50 ~ 17.50 kUA/L), class 4 (17.50 ~ 50.00 kUA/L), class 5 (50.00 to ~ 100.00 kUA/L) and class 6 (≥ 100.00 kUA/L).