Statistical methods for quality control of dose calibrator in nuclear medicine

Abstract

One of the successful treatment of patients in the field of Nuclear Medicine (NM) is by giving the right and accurate dose according to the type of cancer, stage, volume and size of cancer cells. Accurate doses can be achieved by applying Quality Assurance (QA) and Quality Control (QC) to the Dose Calibrator (DC), which is used to measure the dose of radionuclide given to a patient. QA and QC should be applied to the Dose Calibrator to ensure measurement accuracy and traceability. An important reason for establishing statistical QC is to ensure that measurement uncertainty is correctly estimated. Estimation of the uncertainty accompanying measured values can be misleading unless the measurement process is in a state of statistical control. Quality Control aims to monitor performance, identify problems, and take corrective action if things deviate from the habit. Therefore, laboratory data from monitoring results must be available based on the quality system,The main tool for statistical QC is Control Chart (CC). CC has a Central line, which is an estimate of the expected value of the monitored variable, has Warning Limits (which are located between the center line and Control Limits). This paper presents examples of several performance indicators that must be monitored and evaluated in order to know with certainly, the condition of the equipment used for measurement, so It can be concluded that the tool is in a good condition and ready to use. Data taken from laboratory parameter at least 20 data to meet statistical rules. Several performance indicators were Zblank, Zrep, ZCRM. and Control Chart. If the performance indicators of the device were in between Lower Warning Limits (LWL) and Upper Warning Limits (UWL), then the instrument was in a good condition/stable. Three types of CC were presented in this paper: X-chart, X¯ and R-chart. Staffs of laboratory can choose one of the CCs that can be applied in their laboratory.