The word validation is related to the reliability of an analytical method. The purpose of method validation is to ensure that an analytical method is reliable, accurate, and suitable for its intended purpose. Validation provides scientific evidence that the method consistently produces accurate and reproducible results, which are essential for making informed decisions in research, quality control, and regulatory compliance.

Parameters Evaluated During Method Validation

• Specificity: Assesses the ability of the method to accurately measure the analyte of interest in the presence of many other potential interfering substances which exist in the same solution. It ensures that the method is selective and can differentiate between the analyte and other compounds.
• Accuracy: Evaluates how close the measured results are to the true or reference values. It is usually determined by a recovery study, where the standard is spiked in a known amount and recovery is calculated with spiked concentration and found concentration.
• Precision: Refers to the repeatability and reproducibility of the method. Repeatability measures the variation when the same analyst and equipment perform the analysis multiple times, while reproducibility assesses variation between different analysts, instruments, and laboratories.
• Linearity: Tests the relationship between the concentration of the analyte and the detector response over a specified range. It ensures that the method can accurately measure a wide range of analyte concentrations.
• Range: Defines the concentration interval over which it has been demonstrated to be accurate, precise, and linear. It should cover the expected concentration range of the analyte in the samples.
• Limit of Detection (LOD) and Limit of Quantitation (LOQ): LOD is the lowest concentration of the analyte that can be detected but not necessarily quantified. LOQ is the lowest concentration that can be both reliably detected and quantified with acceptable accuracy and precision.
• Robustness: Assesses the method's reliability in the face of minor variations in experimental conditions, such as changes in temperature, mobile phase composition, or flow rate.