Elementi utili per implementare un sistema per il controllo dell'accuratezza dei risultati nella diagnostica di SARS-COV-2 (RNA virale, antigeni e anticorpi) [Useful elements for implementing a system to control the accuracy of results in the diagnosis of SARS-CoV-2 (viral RNA, antigens and antibodies)]

As SARS-CoV-2 swiftly spread globally becoming a pandemic, the urgent need to provide a laboratory diagnosis of the infection - to allow both the clinical management of individual patients and to monitor the outbreak in the community by health authorities - arose. This resulted in a rapid development of diagnostic tests - promptly available on the market - including methods for the direct detection of the virus in biological samples (molecular and antigenic tests) and for indirect detection by documenting a contact with SARS-CoV-2 (serological antibodies tests). To fast-track the availability of these tests, an "emergency" authorization was issued for their use in medical laboratories, which then resulted in the urge to verify their reliability and to monitor carefully their performances, in order to avoid the risk to provide inaccurate results. This document illustrates the main potential sources of error, which can be pre-pre-analytical (i.e. test utilization in an incorrect diagnostic window), pre-analytical (i.e. incorrect collection, manipulation, sample transport and storage), analytical (i.e. pipetting errors during manual sample dispensing, incorrect RNA extraction, cDNA synthesis and amplification) and post-analytical (i.e. incorrect test report and interpretation). Furthermore, the key elements for creating a system to keep continuously under control these potential sources of error are presented, both implementing an adequate control of the entire process and a system for monitoring the analytical quality, where Internal Quality Control plays a crucial role.