Figure 1. Observed iohexol log-concentration versus time curve for Dog 18, together with estimated simple linear regression line (solid) and 95% CI (dashed).  Using the single compartment model, the estimated AUC=126 (Equation (2)), estimated GFRS=2.15 (Equation (4)), standard error of GFRS=0.11 (Equation (5)), and the 95% CI is (0.51, 0.75) (Equation (10)).