Laboratory data

Four laboratories are routinely responsible for SARS-CoV-2 PCR testing within the Northern DHB Region of New Zealand: LabPLUS Auckland City Hospital, Auckland DHB (Site A); Labtests, Community Pathology Services Provider (Site B); Middlemore Hospital, Counties Manukau DHB (Site C); and North Shore Hospital, Waitematā DHB (Site D). A retrospective review of laboratory data was undertaken for all SARS-CoV-2 PCR tests performed by these sites between 12 February 2020 (the date SARS-CoV-2 PCR testing commenced in the Northern DHB Region, at Site A) and 8 June 2020. Extracted laboratory data from each site for the above study period included: total number of samples tested; sample types; collection dates; SARS-CoV-2 PCR results; and Ct values for positive results. A variety of in-house and commercial SARS-CoV-2 PCR testing platforms were used by the four study sites during the study period. A comparison of Ct values between assays and targets was not an aim of the present study, as this has already been undertaken elsewhere [see local and regional external quality assurance (EQA) program reports], and thus data on the individual assays and targets used was not collected.