How can I do crossover studies on a pHOx (Plus, Plus L, Basic,) and CCX analyzer?
The object of doing crossover studies is to ensure instrument performance while establishing the range for a new lot number of control material. The old lot number’s performance has already been established. This is used as the “constant”. The new lot number’s performance has not been established. Changes in the recovery of the new lot number must be compared with the old lot to determine if the changes are valid. The pHOx and CCX line of analyzers are designed to be run with one lot number of internal controls onboard. Design constraints do not allow for more than one lot number of internal controls to be running at a time. However, the instrument is designed to enable a lot of external controls to be run concurrently with the internal controls. Therefore, when establishing the range for a new lot number of internal controls, it is recommended that they be run against a lot number of external controls for which the performance has already been characterized.
