The dark line in the middle of the boxes is the median of IL-33.

<p>Half of the cases have a value greater than the median, and half have a value lower. The bottom of the box indicates the 25th percentile while the top represents the 75th percentile. The points are <b>outliers,</b> while asterisks or stars indicate <b>extreme outliers.</b> p1 (the p value between the three groups) was computed by one-way ANOVA, while p2, p3, and p4 were computed by Mann-Whitney U-test.