Laboratory and imaging
Levey Jennings chart
A Levey Jennings chart is a quality control chart on which a laboratory plots successive control results against their established mean, with lines at 1, 2 and 3 standard deviations, so that shifts, trends and outliers become visible.
Why it matters
A single control value says little; a series shows whether a method is stable. Levey and Jennings introduced statistical control methods to clinical laboratories in 1950, building on the work of Walter Shewhart [1][3]. The chart remains the basic tool of laboratory quality control and one of the first records an auditor examines.
Key points
- The mean and standard deviation should come from the laboratory's own control data; WHO's handbook uses a set of 20 control values [2].
- Values printed by the manufacturer should not replace the laboratory's own mean and limits [1].
- A shift is an abrupt change after which results cluster on one side of the mean; a trend is a gradual movement in one direction [2].
- Westgard rules are applied to the plotted points to accept or reject each run.
In Moana
MOANA LIS plots control results on Levey Jennings charts, applies Westgard rules and keeps the QC history available for review and audit.
Sources
- Basic QC practices: lesson on Levey Jennings charts and control rules, Westgard QC, accessed 2026
- Laboratory quality management system: handbook, World Health Organization, 2011
- A historical perspective of quality control, Medical Laboratory Observer, 2025
Read the guide: Laboratory Quality Control: Westgard Rules and Levey Jennings Charts
In the platform: MOANA LIS
Related terms: Westgard rules, Laboratory information system, Specimen tracking
Updated 2026-11-03. Written under Moana’s editorial standards.