[Adoption of a biomarker in clinical practice: from bench to bedside]

Although numerous diagnostic and/or prognostic biomarkers are proposed in the literature, only a limited number of them are finally used in daily practice. The necessary steps to prove their clinical interest include: 1) an exhaustive clinical and statistical evaluation demonstrating not only the added value of the marker with regard to the existing validated tools but also the modification of the clinical practice induced by the knowledge of the result of the biomarker; 2) an evaluation of the pre-analytical, and analytical performances of its measure necessary to the reliability of the results; 3) an evaluation of its biological variation. These steps are a major prerequisite to an effective, reliable and optimal clinical interpretation of the biomarker, and should be validated for each routine biomarker.