Cycle threshold (Ct) in SARS-CoV-2 RT-PCR

A guide for health protection teams about interpreting Ct in real-time, reverse transcription polymerase chain reaction (RT-PCR) assays performed for Sars-CoV-2.


Understanding cycle threshold (Ct) in SARS-CoV-2 RT-PCR: a guide for health protection teams

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This document outlines how health protection teams should report and apply Ct values for clinical interpretation and actions only in cases where the linearity, limit of detection and standard quantification curves are assured.

Published 28 October 2020