How to read a report with a reference range column
In this common layout, the reference range sits in its own column beside each result. To read it, go across the row: the result, then the unit, then the range for that lab. Compare your result with the range printed on the same row [CLSI, 2010].
Last reviewed: 2026-08-16
Where does the reference range sit?
The range is usually the column just to the right of your result and unit. It shows the usual band for that test at that lab.
Because it sits on the same row, you can compare your value with its range at a glance.
How are out-of-range values shown?
Most reports in this layout add an H or L flag, or print the value in bold or red, when it sits outside the range.
The flag is a prompt to look closer, not a sign that something is wrong [CLSI, 2010].
Does this layout show previous visits?
Often not. This simple layout usually shows one visit at a time.
If you want to see a trend, keep your earlier reports so your doctor can compare them.
Frequently asked questions
- Which column is my result?
- Usually the first number column, to the left of the unit and range. Check the column headings to be sure.
- Why is the range next to every test?
- Each test has its own usual band, so the range is printed per test, on the same row as the result.
- Is the method shown in this layout?
- Sometimes. If a method column is present, it names the technique used. If not, the layout keeps to result, unit and range.
- How do I compare two of these reports?
- Compare each result with the range on its own report, because a different lab may use a slightly different range [CLSI, 2010].
Sources
- CLSI (2010) — Clinical and Laboratory Standards Institute (reference intervals and report presentation)
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