The primary tracking method was the Levey-Jennings chart
for graphing the analytical results.
The probability of the multirule procedure for error detection is much improved over the use of the Levey-Jennings chart
having a [+ or -]3 SD limit for determining acceptability of QC data.
Regardless of how the control limits are established, a Levey-Jennings chart
still operates as a statistical control.
Through this repetition of calculated numbers, the framework of the Levey-Jennings chart
is drawn--the continuous horizontal lines that represent the mean and the mean 2 SD.
Westgard rules and Levey-Jennings charts
are the statistical tools typically used by clinical labs.
Mention is made of Levey-Jennings charts
and Westgard Rules but there is really no mention of how to use these tools in the context of day-to-day blood gas laboratory operation.
In today's environment, it is not possible to use paper Levey-Jennings charts
in which laboratorians manually plot the QC results or manually enter results in long spreadsheets.
The authors suggest that when the same control material is used in multiple runs, selected numeric results can be tracked over time using Levey-Jennings charts
to visualize drift or shift.
Ranges and limits for quality control and system functionality may be recorded manually or by using the monitoring software, which accepts data from the aggregometer and generates Levey-Jennings charts
for review and evaluation of system performance based on West-gard rules for low-volume tests.
plotting QC results on Levey-Jennings charts
and application of Westgard Rules).
When used routinely with traditional tools such as Levey-Jennings charts
and Westgard Rules, the laboratory is alerted to test system errors so corrective action can be performed before system failures occur.
You (the lab manager) have in place the Westgard Rules in some form or another, with Levey-Jennings charts
posted or in a notebook somewhere for the inspector.