Evidence-based approach to harmonised reference intervals

Area of Science:

• Clinical Chemistry
• Laboratory Medicine
• Evidence-Based Practice

Background:

• A significant gap exists between evidence-based medicine principles and the practical application of reference intervals in clinical settings.
• Variations in reference intervals across laboratories, even with identical methods, can lead to physician confusion and complicate patient monitoring.
• Discordant laboratory data due to differing reference intervals hinders effective patient assessment and care.

Purpose of the Study:

• To demonstrate an evidence-based approach for harmonizing laboratory reference intervals.
• To highlight factors influencing reference interval determination and the importance of consistency.
• To advocate for the adoption of harmonized reference intervals to improve clinical decision-making.

Main Methods:

• Discusses key factors influencing reference interval determination, including population selection, biological variability, partitioning, sample collection, and analytical aspects.
• Explores the merits and limitations of a priori and a posteriori approaches for establishing reference intervals.
• Emphasizes the validation of indirect a posteriori methods as a practical alternative for laboratories.

Main Results:

• Identifies numerous factors that contribute to the variability of reference intervals across different laboratories.
• Presents harmonized reference intervals as a solution to mitigate confusion and improve diagnostic accuracy.
• Highlights the feasibility of using validated indirect a posteriori methods for harmonizing intervals.

Conclusions:

• An evidence-based approach is essential for harmonizing reference intervals and bridging the gap between theory and practice.
• Harmonized reference intervals are critical for enhancing the reliability of diagnostic information and supporting physician decision-making.
• Continuous application of evidence-based practices in establishing harmonized reference intervals is necessary to meet physician quality expectations.