Laboratories that perform nonwaived testing must verify that they can obtain performance specifications comparable to those established by the manufacturer.
- Generally this can be accomplished by doing split-sample comparison studies (a technique where a single patient sample is split into two aliquots - one is tested using the primary method, while the other is sent to a lab that uses an appropriate comparison method) to estimate any inaccuracy or bias, plus linearity studies to estimate imprecision and determine the reportable range.
- The laboratory can do studies to determine its own reference ranges, or the laboratory director can document that the manufacturer's ranges are appropriate (after reviewing the demographics of the laboratory's target patient population).
- Note: For those laboratories performing nonwaived tests that have been modified or developed in-house, additional verification studies are required. (Refer to CLIA requirements, often detailed within laboratory accreditation checklists.)
