Background: The Beckman Coulter AU 700 clinical chemistry analyzer is a widely used instrument in high-volume laboratory settings. Its long-term stability and measurement accuracy are critical for ensuring reliable diagnostic results. This study evaluates the analyzer’s performance using sigma metrics over a six-month operational period.
Objectives: To assess the long-term measurement stability of the Beckman Coulter AU 700.To evaluate operational factors such as reagent evaporation, carryover, calibration recovery and mechanical parameters (e.g., syringe pressure).To determine if the system maintains a sigma performance level above 4.5.To inform strategies for optimizing internal quality control (IQC) and reducing associated operational costs.
Materials and Methods: A prospective process evaluation was conducted from May to October 2023 at Meenakshi Labs, Madurai. Daily data were collected on reagent stability, calibration accuracy, IQC performance, and equipment downtime. Sigma metrics were calculated for each parameter using the formula: Sigma = (TEa − Bias) / CV. Descriptive and inferential statistical methods, including confidence interval analysis, were applied.
Results: The AU 700 demonstrated exceptional measurement stability with an overall sigma score of 99.89%. Key findings include: reagent evaporation (0.75%, sigma = 4.95), carryover (0.00047%, sigma = 5.92), calibration recovery errors (0.1982%, sigma = 4.38), QC outliers (0.6815%, sigma = 3.97), syringe pressure outliers (0.04629%, sigma = 4.82), and zero instances of reagent contamination or system temperature failures (sigma = 6). Equipment downtime was minimal (0.05787%, sigma = 4.75).
Conclusions: The Beckman Coulter AU 700 exhibits high reliability and operational efficiency in high-throughput laboratory settings. Its consistent sigma performance above 4.5 across most parameters supports potential reductions in IQC frequency without compromising test accuracy. Some areas, such as QC outliers and calibration recovery, may benefit from process enhancements.
