The technique of the functional test of the liver by means of the indocyanine green (ujoviridine) test suggests to express the results of the test as a result of clearance on the basis of the slope-clearance. 2. The analysis of the curve of disappearance of the test substance in the serum could not always be traced back to a simple exponential function in a group of clinically healthy control persons (10 women at the age of 10-24 years). For the better estimation of the slope-clearance, therefore, the rinsing effect of the liver should be preferred by means of the analysis of a composed (twofold) exponential function. 3. In the two investigation methods the results of the clearance values were not symmetrically distributed so that as parameters of estimation at first only the mean values of density are used. 4. According to this only orientating study the values of the ujoviridine clearance are below 720 ml/min, assuming a simply exponential rinsing function, or 500 ml/min, respectively, taking as a basis the composed exponential rinsing function below the mean values of density.