How Many Medically-Unreliable Results (MURs) Should a Medical Laboratory Be Allowed to Report?

Are you thinking “What???   Labs are allowed to report bad results???”  Should they not aspire to report zero Medically-Unreliable Results?  Before we discuss that, let’s talk today about the definition of a Medically-Unreliable Result.

CLSI EP23A “Medical Laboratory Quality Control based on Risk Management” defines an incorrect result as a result that does not meet the requirements for its intended medical use; In the case of quantitative test procedures, a result with a failure of measurement that exceeds a limit based on medical utility.

EFQLM (European Federation of Clinical Chemistry and Laboratory Medicine) provides guidelines and recommendations that aim to ensure the accuracy and reliability of laboratory test results, ultimately improving patient care and safety.  EFQLM encourages the selection of allowable error limits based on the clinical impact of the laboratory test results. These limits are not arbitrary but are determined by considering the effect of analytical performance on clinical decision-making and patient outcomes. The goal is to set AE limits that allow for accurate interpretation of test results to aid in the proper diagnosis, treatment, and monitoring of patients.

A few strange things you should know about medical laboratory quality control include:

1. Despite the fact that everyone recommends the use of medical goals, few laboratories actually use these meaningful allowable error limits, most labs actually choose to evaluate their performance against regulatory or proficiency goals instead.
2. The level of quality required by regulatory bodies differs greatly between political jurisdictions
   2. For serum calcium levels, while most labs in Europe strive to meet a limit of +/- 2.5% based on biological variation, labs in the USA are “allowed” an error limit of +/- 1.0 mg/dL which is equivalent to 8.5% to 13.5%.
   3. Recommended TEa limits for potassium range from 6% to 16% and 0.2 to 0.5 mmol/L.

Points to ponder today:

1. Do clinical requirements for the intended medical use of lab tests differ by political jurisdiction?
2. If patient need is similar, should laboratory quality requirements be similar?
3. Should inspection agencies verify that laboratories are using medical goals?
4. Should clinicians and patients know the level of quality each lab chooses to control?
5. What can be done to encourage the adoption of best practices from CLSI and EFQLM
6. How many Medically-Unreliable Errors should a lab be ‘allowed’?
   1. Watch for upcoming polls and blogs with case studies.

#CLSI #EFQLM #LabQuality #ClinicalOutcomes #Risk