Laboratory Test Literacy Guides
Search plain-language guides on blood tests, metabolic and heart health, thyroid markers, preventive screening and how to read any lab report.
How to Read a Laboratory Result
Every line on a report is built from the same five parts. Read left to right.
Result
Unit
Reference interval
Flag
Clinical context
Your measured value, such as 5.4.
What the number counts, such as mg/dL.
The laboratory's comparison range for its method.
A marker such as H or L meaning outside that range.
Your history, symptoms and medications, weighed by a clinician.