Levey-Jennings Control Limits: Mean, SD and CV From a QC Series
Levey-Jennings mean, SD, CV and control limits at 1, 2 and 3 SD from a series of control results.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Control results, one per line
- 100.2 98.7 101.5 99.8 100.9 97.6 102.3 100.1 99.4 101.0
- The laboratory's minimum count for setting limits
- 10
Result: Mean 100.15, SD 1.375, CV 1.37% over 10 results.
The tool opens with these values already filled in. Replace them with your own.
What you enter
- Control results, one per line (a date or run label and a comma first is allowed)
- The laboratory's minimum count for setting limits (optional)
How this is calculated
Citation
Stated arithmetic: mean, sample standard deviation (n - 1), coefficient of variation, and limits at the mean plus and minus 1, 2 and 3 SD. No primary source; the chart takes its name from Levey and Jennings, whose paper was not opened.
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.