Overall Accuracy.In addition to the matrix effect and sample preparation error,

method accuracy can also be affected by calculation error: for example, difference

in relative response, significant y-intercept, and nonlinearity. Therefore, a more

vigorous approach is to determine the overall accuracy, which incorporates the

effect from all aspects of the method:

žMatrix effect

žSample preparation

žCalculation error

In this approach, similar to the determination of intrinsic accuracy, the accuracy

solutions are prepared by spiking a known quantity of authentic samples and drug