Pre-analytical rejection rates of clinical samples based on patients’ health status


Background and objective: The pre-analytical rejection rate is the proportion of samples rejected at the stage that includes the initial procedures of the testing process performed outside the laboratory walls by healthcare professionals. This study aimed to evaluate the pre-analytical rejection rate by considering the health status of the patients and the sample types and to examine the measures that can be taken against it. Methods: The data of the samples that came to the laboratory for analysis for one year were included. These data were categorized according to sample types in complete blood count, biochemistry, hormones, urine, blood gases, coagulation, erythrocyte sedimentation rate (ESR), glycosylated hemoglobin (HbA1c). It was also categorized by emergency, outpatient, inpatient, and critically ill status. Considering the health status of the patients, the pre-analytical rejection rates determined in these sample types were compared. Results: Complete blood count (0.40%) in emergency patients, HbA1c (0.78%) in outpatients, biochemistry (0.62%) in inpatients, hormones (0.29%), urine (6.19%) blood gases (1.03%), coagulation (1.26%), ESR (3.23%) in critical patients, sample types had the highest pre-analytical rejection rate. Conclusions: The source of causes that affect pre-analytical rejection rates, such as hemolyzed sample, clotted sample, or insufficient sample, may be due to the patient's bed rest, critical or emergency. An underlying disease, treatment, or frequent phlebotomy may also be a factor. The source of the causes that affect the pre-analytical rejection rates, such as incorrect request, incorrect registration, and incorrect tube, can usually be attributed to non-laboratory healthcare personnel.