A longitudinal study assessing Aspergillus polymerase chain reaction (PCR) performance through participation in external quality assessment schemes from 2019 to 2022.

Aspergillus polymerase chain reaction (PCR) now employs standardised methodology and commercial options, with clinical performance validated through meta-analyses. The long-term availability of external quality assessment schemes drives performance and provides a currently untapped source of technical data. The Fungal PCR initiative and the Quality Control for Molecular Diagnostics (QCMD) combined forces to evaluate data from the Aspergillus PCR QCMD schemes between 2019 and 2022. Analysis showed inferior detection of non-fumigatus Aspergillus species (i.e.,Aspergillus niger) compared with A. fumigatus. Longitudinal evaluation showed the use of 'in-house' PCR methods by new participants when testing plasma generated lower positivity rates compared to commercial assays.