Minimum Retesting Intervals
Minimum retesting intervals (MRIs) define the recommended minimum time before a laboratory test should be repeated in the same patient. They are intended to support appropriate use of laboratory testing and to reduce unnecessary repeat requests where results are unlikely to change clinical management.
Our MRI criteria are based on national guidance from the Royal College of Pathologists (G147: National Minimum Retesting Intervals in Pathology) along with locally approved intervals. For the tests listed in the table below, repeat requests received within the defined interval will normally be rejected by the laboratory system. Patients aged 17 years and under are excluded from these rules, and additional clinical exceptions may apply.
Minimum Retesting Intervals download here
These intervals are intended as guidance and do not replace clinical judgement. For advice regarding a specific patient or rejected request, please contact the Duty Biochemist at rwh-tr.bcpsdutybiochemist3@nhs.net or on 01902 695290.

