Q&A ON VALIDATION OF ANALYTICAL PROCEDURES – ICH Q2 GUIDELINE PART -2
Question 1:
What does accuracy of an analytical procedure express?
Answer 1:
The accuracy of an analytical procedure expresses the closeness of agreement between the value accepted as a true or reference value and the value found. It is sometimes referred to as trueness.
Question 2:
What does precision of an analytical procedure express?
Answer 2:
The precision of an analytical procedure expresses the closeness of agreement between a series of measurements obtained from multiple sampling of the same homogeneous sample under prescribed conditions.
Question 3:
What are the three levels at which precision may be considered?
Answer 3:
Precision may be considered at three levels: repeatability, intermediate precision, and reproducibility.
Question 4:
What does repeatability express in terms of precision?
Answer 4:
Repeatability expresses the precision under the same operating conditions over a short interval of time and is also known as intra-assay precision.
Question 5:
What does intermediate precision express?
Answer 5:
Intermediate precision expresses within-laboratory variations, including differences between different days, analysts, equipment, etc.
Question 6:
What does reproducibility express?
Answer 6:
Reproducibility expresses the precision between laboratories and is typically applied to collaborative studies for standardization of methodology.
Question 7:
What is the detection limit of an individual analytical procedure?
Answer 7:
The detection limit of an individual analytical procedure is the lowest amount of analyte in a sample that can be detected but not necessarily quantitated as an exact value.
Question 8:
How is the quantitation limit of an individual analytical procedure defined?
Answer 8:
The quantitation limit of an individual analytical procedure is the lowest amount of analyte in a sample that can be quantitatively determined with suitable precision and accuracy.
Question 9:
What does the linearity of an analytical procedure refer to?
Answer 9:
The linearity of an analytical procedure refers to its ability, within a given range, to obtain test results that are directly proportional to the concentration (amount) of analyte in the sample.
Question 10:
How is the range of an analytical procedure defined?
Answer 10:
The range of an analytical procedure is the interval between the upper and lower concentration (amounts) of analyte in the sample, including these concentrations, for which it has been demonstrated to have a suitable level of precision, accuracy, and linearity.
Question 11:
What does the robustness of an analytical procedure indicate?
Answer 11:
The robustness of an analytical procedure indicates its capacity to remain unaffected by small, deliberate variations in method parameters and provides an indication of its reliability during normal usage.