Setting process control limits for enzyme tests in serum

Area of Science:

• Clinical Chemistry
• Laboratory Medicine
• Enzyme Assays

Background:

• Modern laboratory equipment offers high precision.
• Current performance-based standard deviations for enzyme testing may be overly rigid.

Purpose of the Study:

• To evaluate the appropriateness of performance-based standard deviations for enzyme testing.
• To discuss alternative methods for setting process control limits.

Main Methods:

• The study reviews current practices in enzyme testing and precision limits.
• It considers the clinical utility of enzyme data and laboratory resources.

Main Results:

• Performance-based standard deviations are not suitable for current enzyme testing precision.
• Existing methods for setting control limits have arbitrary elements but remain usable.
• Tight precision is often unnecessary for common serum enzyme tests.

Conclusions:

• Laboratories should move away from overly rigid, performance-based standard deviations for enzyme testing.
• The choice of process control limits should be tailored to laboratory capabilities and clinical requirements.
• Selecting appropriate control limits ensures efficient resource use and meets medical needs.