Presentation on theme: "Module 6 Lab Exercise I: Quality Control and Construction of Levey-Jennings Charts."— Presentation transcript:
Module 6 Lab Exercise I: Quality Control and Construction of Levey-Jennings Charts
Levey-Jennings Activity Objectives At the completion of this activity, you will be able to: 1.Perform statistical analysis on analyte values from the previous month’s control values, both normal and abnormal levels, to determine Mean, SD, %CV. 2.Draw a Levey-Jennings chart, label the x and y axis correctly, and properly label the LJ chart for documentation and filing. 3.Plot current month’s values daily and evaluate LJ chart for Westgard single rule violations, trends, shifts. 4.Discuss the necessity of Quality Control Result documentation and how they assess precision and accuracy.
Quality Control Exercise #1 Quality control sample measurement is used to test the analytical phase of patient testing. This first exercise provides quality control sample results to calculate statistics and establish a Levey-Jennings chart.
Last Month’s QC Values (Glucose mg/dL) For Establishing the QC Ranges Day 1 68Day 8 80Day Day 2 82Day 9 75Day Day 3 79Day 10 68Day Day 4 69Day 11 77Day Day 5 70Day 12 82Day Day 6 79Day 13 74Day Day 7 80Day Calculate the Mean: __________ 2.Calculate Std Dev: __________ 3.Calculate %CV: __________ 4.Determine + 3 SD Range: ____________ 5. Construct graph & plot all points
Instrument: _________________Test: ____________________Units: ________ Method: ____________________Month/Year: ______________Tech: ________ Control: ____________________Lot #: ____________________Exp: _________ Control Mean: _______________1 Std Dev: ________________ -+3 SD Range: ___________ + 3s - 2 s + 1 s Mean - 1 s + 2 s - 3 s Days
Now Plot the following QC Values (Glucose mg/dL) Day 1 75Day 8 80Day Day 2 73Day 9 75Day Day 3 78Day 10 77Day Day 4 69Day 11 68Day Day 5 70Day 12 82Day Day 6 79Day 13 74Day Day 7 80Day 14 72
This is what the LJ Chart should look like including plotted data
Exercise #2 Evaluate the following QC chart by identifying out of control data, outliers, shifts, and trends
Key QC Lecture Activity #2 3 circled areas and 2 pointers note analytical problems shown by patterns of QC results. What are they?