I have questions: 1. What if you have a value beyond 3SD during the 20 measurements of running IQC? I mean why we run the IQC on a system whose reliability may affect the generation of +-2SD? 2. After running the IQC for 20 days, and getting Mean and SDs, when we make this chart, and then enter new values of controls, will the chart not be affected? 3. Why to use Assayed control when we have to get our own values of SDs? 4. How can we run measurements for 20 days on a QC vial whose stability is 14 days?
mam kindly tell whether lj chart tells about precision and accuracy or lrecison only..? if precision only then how will accuracy we come to know about our controls..?
To know this: read about Gaussian - Mean, SD, CV and Range. formular: SD x (+-SD)+ Mean or SD x (+-SD) - Mean. for example mean = 190.5 , SD= 2, (+-3) is given as range of acceptability. Using the above formular . 2x(3)-190.5 and 2x(3)+190.5. will give you (+-3SD). Hope its clear. i hope someone finds this helpful. 🤩😁
