Analysis of recent pharmaceutical regulatory documents on analytical method validation.

All analysts face the same situations as method validation is the process of proving that an analytical method is acceptable for its intended purpose. In order to resolve this problem, the analyst refers to regulatory or guidance documents, and therefore the validity of the analytical methods is dependent on the guidance, terminology and methodology, proposed in these documents. It is therefore of prime importance to have clear definitions of the different validation criteria used to assess this validity. It is also necessary to have methodologies in accordance with these definitions and consequently to use statistical methods which are relevant with these definitions, the objective of the validation and the objective of the analytical method. The main purpose of this paper is to outline the inconsistencies between some definitions of the criteria and the experimental procedures proposed to evaluate those criteria in recent documents dedicated to the validation of analytical methods in the pharmaceutical field, together with the risks and problems when trying to cope with contradictory, and sometimes scientifically irrelevant, requirements and definitions.