Evaluation of Pre-analytical Process with Quality Indicators and Six Sigma Methodology in the Parasitology Laboratory of a Tertiary Healthcare Center

: Laboratories have important role in decisions related to the patient. Laboratory performance needs to be evaluated to ensure accurate and sustainable laboratory results. Total test process consists of pre-analytical, analytical and post-analytical sub-processes. Most of the laboratory errors occur in pre-analytical process, which is mostly outside the laboratory, and this important situation has to be monitored by laboratory specialists. Although the standard statistical methods in which the frequency is evaluated can reveal which error is more than the others, they cannot determine which error is needed due to the absence of accepted target values. The decision to intervene in errors can only be made according to the targets by evaluating with methods such as six-sigma and quality indicators. Six-sigma method; is a quality management tool that provides information about process performance. Low sigma level indicates variability or errors in the relevant process. Quality indicators have been developed to measure quality and efficiency of laboratory processes. Use of quality indicators is effective in reducing errors, increasing patient safety and helping to meet ISO-15189 requirements. In this study, it was aimed to evaluate pre-analytical process performance in Parasitology Direct Diagnosis Laboratory of Ege University Faculty of Medicine according to the quality targets of International Federation of Clinical Chemistry and Laboratory Medicine Working Group on Laboratory Errors and Patient Safety (IFCC WG-LEPS) and the six-sigma method. The data of rejected samples in our laboratory during the period 2014-2017 were obtained retrospectively from laboratory information system. Errors were classified using laboratory errors classification system. Quality indicators were calculated for each error category and assessed according to IFCC WG-LEPS quality targets. Pre-analytical sigma level was calculated for each year. Our pre-analytical process sigma goal was 4.6. Sigma levels were calculated according to the reasons of rejection and Pareto analysis was performed. All of the rejected samples were pre-analytical process errors. Unacceptable quality indicators according to the IFCC WG-LEPS targets were found as "insufficient sample" in 2015; "insufficient sample" and "inappropriate sample tube" in 2016 and 2017. Our pre-analytical process sigma levels according to the rejection reasons were found to be 4.39, 4.31, 4.11, 4.17, respectively in 2014- 2017. "Improper test request" in 2014, and "insufficient sample" in 2015-2017 had sigma levels below 4.6. In addition "improper test request" in 2014, and "insufficient sample" in 2015, 2016 and 2017 were noticeable in Pareto analysis. In this study, pre-analysis process was evaluated with six sigma method and quality indicators and the areas open for improvement were determined quantitatively. We found "insufficient sample", "improper test request" and "inappropriate sample tube" indicators as inappropriate according to our target values with both quality indicators and six-sigma methods. For this reason, we have planned video conference training focused on error sources for all employees. We consider that risk and number of errors will be reduced and efficiency of whole test process can be increased by evaluating pre-analytical process with accepted methods and monitoring the results. Process evaluation studies with six-sigma and quality indicators are limited in microbiology and parasitology laboratories. We think that laboratory quality is indispensable and this study will be an example for the laboratory specialists who want to evaluate pre-analytical process of their laboratories.