Figure 1.

Plasma levels of soluble transferrin receptor (sTfR) in diabetic and nondiabetic chronic dialysis patients. The boxes represent the interquartile range (IQR), with the upper and lower edges of the boxes representing the 75th and 25th percentiles, respectively. The central horizontal lines within the boxes represent median levels for each group. The vertical whiskers above and below the boxes represent the range of outlying data points up to 1.5 times the IQR; they extend from the box to the highest and lowest values, excluding outliers.