Use a Project to Save Control Chart<br>Lines

Recently, we received the following question:

“I was trying to make my control chart for one analyte. Usually we do a number of tests to collect statistical data and then based on these values the min max lines are plotted on the QC chart. … How am I supposed to do this properly?”

Since the Control Chart Setup dialog allows you to use the analysis’ specifications (result min/max, warning min/max, target) to specify the chart’s control and warning high/low and target lines, you can use this feature to set the lines for your chart. After you have calculated the control high/low values, create a new project whose only purpose is to store these values. Add the analyte to the project then add the control high/low values to the Result Max and Result Min fields for the analyte. Add each additional analyte for which you will create control charts.

To generate your control chart, first select the analyte in the Control Chart Setup dialog then toggle the Rmax and Rmin buttons adjacent to the Control High and Control Low fields in the Control Chart Setup dialog (the state of the buttons is preserved). Now enable the Project option under “Use Analysis Specifications” then select the project you created above and your Result Max and Result Min values for the analyte are automatically inserted in the Control High and Control Low fields. Enter query criteria to locate the analyses to chart then preview the chart. Note that you can also export the control chart to one of the example Excel control chart templates if you want more control over the chart’s appearance.

Note that the project you create to save the control high/low values for each analyte you will chart is only used to store these values in the project setup screen. No samples should be logged for the project and you should name the project appropriately so you know its purpose.