İnvestigation of reasons for rejection due to preanalytical errors of laboratory tests required from primary health care centers providing public health

Objective: Laboratory tests constitute the majority of directed research applications used in primary health care centers. Among these, it is seen that clinical biochemistry tests are the most common ones. The total test process of these tests consists of three parts as preanalytical, analytical and post-analytical phase. In this process, 65-70% of the errors occur in the preanalytical phase. Working healthcare professionals in primary health care centers are non-laboratory operators of preanalytical phase and their awareness of the effects of this phase is very important. In this study, it was aimed to evaluate the frequency of rejection and the reasons for rejection depending on the preanalytical errors of the laboratory tests requested in a one-year period in the institutions providing primary health care services in Ankara. Materials and Methods: It is a cross-sectional study. This research was conducted by analyzing the data of the Public Health Medical Analysis Laboratory, where blood and ürine samples taken between January 1, 2019 and December 31, 2019 in Primary Health Care Centers in Ankara. Data were taken from systematic computer data stores. No other data collection method or form was used. Statistical evaluations were made with IBM SPSS. Mean and standard deviation, minimum and maximum values are reported for continuous variables, frequency and percentage values are given for categorical variables. Chi-square Tests and ANOVA analyzes were used for statistical significance. Results: According to the analyzed data, a total of 3 046 194 samples were evaluated in Public Health Laboratory in 2019, 24 365 samples were rejected due to preanalytical errors and the rejecion rate was determined as 0.80 % of total samples. Reasons for rejections are listed respectively as "Serum hemolysis"(20.2%), "Sample clotted"(18.5%) and "Insufficient sample quantity"(18.5%). On the sample basis(tube), the highest rejection was seen in the Yellow Capped Tube(50.7%) and the least rejection was seen in the Thalesemia Scan Tube(0%). According to the test groups, the most rejection was seen in routine biochemistry with 34%. According to the months, it was determined that the most rejection occurred in January (17.9%) and the least in June(1.9%). Conclusion: In this study, it was found that the rate of rejection due to preanalytical errors in the one-year evaluation of primary care laboratory tests in Ankara was higher compared to the literatüre. It was observed that all values are within the acceptable range according to the quality indicators that can be evaluated from the preanalytical process quality indicators determined by the International Fedaration of Clinical Biochemistry and Clinical Laboratories. In order for all quality indicators to be evalueted, the data must be standardized. In this way, it will be possible to reveal preanalytical errors more clearly and to make the necessary interventions. In order to reduce preanalytical errors and related rejections, it is necessary to organize infrastructure and training activities both in the laboratory and in primary health care institutions. Keywords: preanalytical error, hemolysis, quality indicators, training, primary health care