Using the Quality Control Chart to Evaluate the Quality of Some Biochemical Tests (Glucose and Creatinine) in Some Private Medical Laboratories in Brack Alshatti Area

Abstract

Clinical chemistry laboratories play a critical role in healthcare, contributing to approximately 70% of medical decision-making through the provision of accurate and reliable test results. Given this significant impact, ensuring and continuously monitoring the analytical quality of these laboratories is essential. This study aimed to assess the analytical performance of selected biochemical parameters—namely, creatinine and glucose—in three private clinical laboratories located in the Brack Al-Shatti region, Libya. Quality assessment was conducted using Levey-Jennings control charts based on commercial quality control (QC) materials. Quality control charts were established for each laboratory, and performance was evaluated based on Westgard multirule criteria. The analysis revealed violations of the following rules: 12s (warning rule), as well as 13s and 22s (rejection rules), indicating potential analytical errors or imprecision in test procedures. Despite the long-standing integration of quality control principles in clinical laboratory practice, their application remains suboptimal in many local settings. The findings highlight the need for rigorous implementation of standardized internal quality control protocols, supported by continuous training and oversight, to ensure the reliability of diagnostic results and enhance patient safety.