Four Calls at the Bench

Four scenarios follow, each requiring a defensible next action from a bounded set: recalibrate and document; perform calibration verification for the trigger event; escalate and investigate rather than recalibrate a third time; or report the result as above the validated interval and dilute or refer per the method's instructions, rather than reporting a number the system was never shown to measure accurately.

Scenario 1: a new reagent lot for the glucose method arrives and is loaded this morning. Scenario 2: major preventive maintenance, including replacement of the sample probe, was completed on the same analyzer yesterday. Scenario 3: calibration verification has now failed twice in a row on this method, even after a recalibration was performed between the two attempts. Scenario 4: a patient specimen returns a glucose result flagged above 400 mg/dL, the top of this method's validated measuring interval.

When calibration verification fails, patient protection starts before prolonged root-cause work: stop further reporting or hold the method, then review patient results released since the last acceptable verification to decide whether correction or provider notification is needed. The subsequent investigation reviews reagent, calibrator, and control lot and expiration, maintenance history, repeat testing where scientifically justified, and recalibration. The ordering exercise below works through that sequence.

Repeated failure after a correction attempt is an escalation trigger, not a signal to recalibrate a third time and hope.