Understanding Analytical Error--The Use of Controls and Blind Controls

Nunnally, Brian K.; McConnell, John; McGarvey, Bernard
November 2009
Journal of Validation Technology;Autumn2009, Vol. 15 Issue 4, p56
Academic Journal
The article discusses the use of controls and blind controls in laboratories. Quantitative assays can benefit from a control sample. However, a residual assay does not require a control since variability is not as important. When selecting a control sample, it must be representative of the material being tested. It also needs to be stable over time and should be homogeneous. The usage rate, the usability of control and the amount of available material are the factors affecting the amount of materials needed for a control sample. A nice method for determining the suitability of an assay can be provided by a proper control sample combined with robust control charting.


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