ESTIMATION OF UPTAKE FROM CENSORED URINE EXCRETION DATA

The estimation of radionuclide uptake often involves consideration of measurements of urine excretion which may include some values reported as below the limit of detection (LOD). Data sets which contain below LOD data as well as positive results are known as censored data sets. A simple method which uses the information contained in censored data to estimate uptake is described. A Monte Carlo technique has been used to investigate the accuracy and the efficiency of the method using si mulated data sets with increasing numbers of LOD data points.