Determination and Evaluation of Quality Control Processes Using Six Sigma Metrics on Major Tests at Mzimba South District Medical Laboratory, Malawi

This observational study on retrospective and prospective data for 35 months examined whether the laboratory department at Mzimba district hospital ensures a total quality management across all its processes is achieved using the sigma-metric.Bias and bias percentage were calculated using true values collected from external quality assurance results and package inserts.Total allowable errors for each parameter were extracted from the Clinical Laboratory Improvement Amendment (CLIA), with the Coefficient variations extracted from past statistical control values of the same lot numbers and external quality assurance results.Six sigma metrics formula was used for metrics calculation of all 23 parameters for this entire medical laboratory department.All 23 EQC parameters had less than 5 sigma metrics at p value of 0.0000. White blood count (WBC), Mean cell haemoglobin concentration (MCHC), and platelet (PLT) had sigma metrics between 4-5. Red blood cells (RBC), hematocrit (HCT), Mean cell volume (MCV), and haemoglobin (HGB) had sigma metrics < 3.Alkaline phosphatase (ALP), total protein (TP) had sigma between 1-3.Albumin (ALB), total bilirubin (BIL T), direct bilirubin (BIL D), alanine aminotransferase (ALT), aspartate transaminases (AST), Gamma Glutamyl Transaminase (GGT), creatinine (CR) and UREA had sigma metrics less than 3. Low and High parameters for both Viral load and SARS-Cov-2 scored less than 1 sigma metrics.On comparisons between years none of the parameters performed satisfactorily.There is a need to meet high class performance on quality control processes across all quality management system essentials.