What in particular is the process chain in a laboratory subject to?

Laboratory testing is best understood as atotal testing process(from test ordering through specimen collection, analysis, and result reporting). Across this chain, error risk is heavily influenced byvariability—especially inpre-analytical steps(patient identification, tube labeling, specimen handling, transport conditions) andpost-analytical steps(timely reporting, critical value communication, interpretation). Risk management objectives emphasize controlling variation through standard work, barcoding, competency training, environmental controls, and quality indicators for each phase. Importantly, many lab failures arise outside the analyzer itself; focusing only on the analytical instrument misses major sources of harm. Reducing variability improves reliability, reduces redraws and diagnostic delay, and supports defensible performance in accreditation and event review. In short: the lab process chain is a high-volume, multi-step clinical production system—variation is inevitable, but unmanaged variation increases patient safety risk.