The reference ranges for PEth have changed - why is this?

Why have the reference ranges changed?

From 1 April 2026, the PEth reference ranges were updated following recommendations and scientific consensus within the forensic toxicology community, including guidance from professional organisations such as the Society of Toxicological and Forensic Chemistry and other expert groups. The revised ranges are designed to improve the accuracy and consistency of how PEth results are interpreted. Results issued before 1 April 2026 were interpreted using the best guidance available at that time.