Quality indicators to detect pre-analytical errors in laboratory testing.

The identification of reliable quality indicators (QIs) is a crucial step in enabling users to quantify the quality of laboratory services. The current lack of attention to extra-laboratory factors is in stark contrast to the body of evidence pointing to the multitude of errors that continue to occur, particularly in the pre-analytical phase. The ISO 15189: 2012 standard for laboratory accreditation defines the pre-analytical phase, and recognizes the need to evaluate, monitor and improve all the procedures and processes in the initial phase of the testing cycle, including those performed in the phase of requesting tests and collecting samples, the so-called "pre-pre-analytical phase". Therefore, QIs should allow the identification of errors and non-conformities that can occur in all steps of the pre-analytical phase. Traditionally, pre-analytical errors are grouped into identification and sample problems. However, appropriate test requesting and complete request forms are now recognized as fundamental components in providing valuable laboratory services. The model of QIs developed by the Working Group of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) includes indicators related to both identification and sample problems as well as all other pre-analytical defects, including those in test requesting and request forms. It, moreover, provides the framework (with objective criteria) necessary for promoting the harmonization of available QIs in the pre-analytical phase.