After a quality control laboratory (QCL) has been included in the WHO List of Prequalified Quality Control Laboratories, it should inform WHO immediately of any changes – by submitting an updated laboratory information file – that it has implemented to its services or operations that may have an impact on its prequalification status. These changes include changes to its facilities, equipment or key personnel).

Every prequalified QCL will be re-evaluated on a routine basis at regular intervals (annually) or earlier (if WHO receives information that indicates that re-evaluation is necessary).

To enable WHO to carry out re-evaluation, all prequalified laboratories are requested to submit a brief annual report on their activities. The report should cover all activities related to quality control of medicines undertaken during the preceding calendar year and be submitted before the end of March of the following calendar year. 

The frequency of WHO re-inspection of QCLs is determined by its assessment of the quality risk management factors relating to each QCL. See also Post-prequalification Procedures.

WHO may suspend or withdraw a prequalified QCL from the WHO the List of Prequalified Quality Control Laboratories if it receives of identifies evidence of non-compliance with the WHO recommended quality standards for such laboratories and/or the prequalification procedure.