Qualification: a conclusion that the biomarker data support use of the biomarker in drug discovery, drug development or post approval studies and where appropriate, in regulatory decision making. 

Validation: procedure establishing documented evidence that a process or system, when operated within established parameters, can perform effectively and reproducibly to produce a biomarker that meets its pre-determined specifications and quality attributes. The objective of the method validation is to “demonstrate that an analytical procedure is acceptable in terms of accuracy, precision, selectivity, sensitivity, reproducibility, and stability for its intended application.