Estimate the precision of the measurement procedure.
The worksheet opens showing 3 columns. The Sample column identifies the levels of the analyte in the sample (3 levels). Run identifies the day number of each run (5 runs). Ferritin (ug/L) identifies the measured value for 3 replicates of sample in each run.
The analysis report opens.
The variability plots show a simple visual assessment of the closeness of agreement between the measured quantity values. The purple lines show the mean of each run and the blue line the overall grand mean, allowing you to see the variation between and within each run.
(click to enlarge)
You should observe the scatter of the points to ensure there are no obvious problems. If the data appear to be unusable, stop the evaluation and begin an expanded evaluation of the sources of measurement error or contact the manufacturer.
The abbreviated variance components table shows precision expressed numerically as the standard deviation (SD) and coefficient of variation (CV).