A survey on sample matrix and preanalytical management in clinical laboratories.

The vast majority of biochemistry tests is traditionally performed using either serum or heparinized plasma. Since little information is available on organization of clinical chemistry areas and type of biological samples used for this type of testing, the SIBioC Study Group on Extra-analytical variability planned a survey to be delivered to the members of the society. The questionnaire, consisting of 10 questions, was delivered by two newsletters and published on the SIBioC website for one month. Overall, 229 replies were collected from ~3000 society members. The most relevant aspect emerged from the survey was that serum not only was the most common biological matrix used for clinical chemistry tests (82% of responders), but it was also regarded as the ideal biological matrix (76% of responders). In 80% of cases, clinical chemistry testing was performed using blood collected in tubes containing a separator. Unlike ordinary testing, urgent analyses were performed using serum only in 58% of cases. The use of blood tubes with separator was also more frequent for urgent chemistry testing (64% of responders). A physical integration between clinical chemistry instruments was reported in approximately half of cases, whereas integration with preanalytical modules was reported to be slightly lower (45% of responders). The availability to change the biological matrix by the majority of responders demonstrates a substantial awareness that a major degree of harmonization should be pursued in the preanalytical phase.