Reference intervals for the P-Albumin bromocresol purple method

Area of Science:

• Clinical Chemistry
• Laboratory Medicine
• Biochemistry

Background:

• Accurate reference intervals are crucial for interpreting laboratory test results.
• Establishing unique reference intervals is resource-intensive, leading to the adoption of shared intervals like NORIP in Nordic laboratories.
• The bromocresol purple (BCP) method is commonly used for P-Albumin testing.

Purpose of the Study:

• To compare existing NORIP P-Albumin reference intervals with current laboratory results obtained using the BCP method.
• To assess the suitability of NORIP intervals for P-Albumin measurements in Nordic clinical laboratories.
• To propose updated reference interval limits based on current analytical methods.

Main Methods:

• Utilized external quality control reports to analyze P-Albumin level changes between BCP and BCG methods.
• Developed an algorithm to extract and isolate healthy subject populations from laboratory information systems.
• Applied parametric and non-parametric statistical methods to evaluate P-Albumin test result data.

Main Results:

• The indirect evaluation method demonstrated a significant discrepancy between NORIP P-Albumin reference intervals and results from current BCP methods.
• Analysis revealed that NORIP intervals are not appropriate for P-Albumin measurements using contemporary BCP techniques.
• The study identified a need for revised reference intervals tailored to current analytical practices.

Conclusions:

• The NORIP reference intervals for P-Albumin are not compatible with current bromocresol purple (BCP) methodologies.
• A significant need exists to re-evaluate and potentially update P-Albumin reference intervals for Nordic laboratories.
• The developed methodology provides a framework for suggesting new, more accurate reference interval limits.