What is a Levey-Jennings Chart?
It is a graph on which analyte quality control data is plotted to provide a visual indication of whether a laboratory test method is working correctly.
- The Levey-Jennings chart usually has the days of the month plotted on the X-axis and the control observations plotted on the Y-axis.
- On the right is the Gaussian or "bell-shaped" curve turned on its side to show the correlation of the curve to the chart (ie, fewer data points should appear on the upper and lower extremities of the chart, since the "bell" is thinner farther from the mean).
- By observing the data plotted in the L-J chart, we can determine if test results are in control and accurate, or if test results are not in control and consequently unacceptable.
- Use of the Westgard, Cumulative Summation Rules, and the Youden plots will help establish an effective error-detecting scheme.