[Analysis of results taken with "tweezers": some pitfalls in clinical biological interpretation]. / Des résultats d'analyses à prendre avec des "pincettes": quelques pièges de l'interprétation en biologie clinique.

Like other medical investigations, laboratory tests are not free from uncertainties or errors which limit their clinical value. Usually two levels of variations are identified: the analytical and biological levels. This paper presents some sources of variations and provides different examples. The concept of reference value is also discussed, as well as the clinician's viewpoint regarding the interpretation of laboratory results.