Glossary
Reference Range
A reference range is the numeric interval printed alongside a lab test result that reflects the range a laboratory considers typical for its testing method and reference population. Values outside this range are often flagged but require clinical interpretation.
How laboratories set reference ranges
Labs establish reference ranges based on their testing method, equipment, and the population sampled during validation. Ranges may differ for age, sex, or pregnancy status.
The range on your report is specific to that lab and that test run. It should be the basis for any high or low flags you see — not generic values from internet search results.
Reference range vs. clinical target
A reference range describes a statistical interval for a population. A clinical target is a goal your clinician sets for you individually — like a target HbA1c discussed in a diabetes care plan.
These aren't always the same. Your clinician may want a value within a tighter band than the printed reference range, or may interpret a flagged value differently based on your full history.
Why this matters for longitudinal tracking
When comparing results over time, check whether the reference range changed between reports. A new lab or updated method can shift the interval and affect how values are flagged.
MedLens+ stores the reference range from each uploaded report so your timeline reflects the source document. Cross-lab comparisons include cautions because ranges and methods may not be directly comparable.