Evaluating analytical quality in clinical biochemistry laboratory using Six Sigma

Area of Science:

• Clinical Chemistry
• Quality Management Systems

Background:

• Six Sigma metrics are increasingly applied in healthcare for performance evaluation.
• Companies like General Healthcare and Siemens utilize Six Sigma in clinical settings.
• This study focuses on applying Six Sigma to a clinical laboratory setting.

Purpose of the Study:

• To evaluate the process performance of a clinical chemistry laboratory using Sigma metrics.
• To determine appropriate analytical quality control strategies for each laboratory parameter.

Main Methods:

• Internal quality control data from a five-month period were collected.
• Sigma metrics were calculated for 20 clinical chemistry parameters.
• Calculations utilized total allowable error, precision, and percent bias.

Main Results:

• Sigma values below 3 were observed for urea and sodium.
• Sigma values between 3 and 6 were found for total protein, creatine kinase (CK), total cholesterol, glucose (GLU), and albumin (ALB).
• Sigma values exceeding 6 were recorded for amylase (AMY), uric acid, high-density lipoprotein-cholesterol (HDL-C), total bilirubin (TBIL), alanine aminotransferase (ALT), triglyceride, aspartate aminotransferase (AST), alkaline phosphatase (ALP), and creatinine (CRE).

Conclusions:

• Amylase exhibited the highest performance with a Sigma value of 19.93.
• Sodium showed the lowest average Sigma value at 2.23.
• Improvement actions are recommended for parameters with Sigma values below 3 to enhance method performance.