Guideline References

Verification of Reference Intervals in the Medical Laboratory — Implementation Guide

The primary standard governing verification of preestablished reference intervals. Specifies the minimum study design (20 reference individuals, single run, single day), the 10% rule for pass/fail determination, and guidance on repeat studies when borderline results are obtained.

Defining, Establishing, and Verifying Reference Intervals in the Clinical Laboratory

The foundational reference interval standard. C28-A3c governs the full establishment of reference intervals (≥ 120 individuals) and provides partitioning guidance by sex, age, and other demographics. Verification studies reference C28-A3c for selection criteria and study design principles.

Accreditation and Regulatory Requirements

CAP and CLIA require documented reference interval verification for quantitative non-waived tests. Verification records must include the study design, reference individual selection criteria, raw data, and the pass/fail determination.