THE REFERENCE RANGE REVOLUTION - WHAT IS DRIVING ALL THE CHANGES?

Course overview

CLIA Regulations require all Clinical laboratories to validate or establish reference limits for all assays before they are put into use for reporting results from patient sample testing. The importance of valid reference limits cannot be overemphasized enough since it is against those limits that clinicians compare the individual patient results to judge if the patient's results are normal or abnormal, high or low, and if further testing or clinical intervention is required. However, in recent years the way reference limits are being developed has changed and clinical laboratories can be caught by surprise that the reference ranges they are using are no longer valid. What has changed is that more laboratory testing reference intervals are being determined by large clinical studies which are seeking to differentiate patients based on such criteria as healthly limits or on probability of disease limits rather than some purely population based criteria such as +/- 2 SD limits around the geometric mean typically employed by clinical laboratories. Examples of laboratory reference limits determined by large clinical studies and medical literature reports include those for assays like total cholesterol, LDL-Cholesterol, glucose, troponin, high sensitivity CRP and high sensitivity D-Dimer. It is not practical for clinical laboratories to validate those clinical study derived reference limits, but it is important to understand how and why these limits differ from the range of analyte values actually measured from the patient population served by the laboratory. This teleconference will bring the attendees up to date with what is happening with laboratory reference limits and how each laboratory can assure that the reference limits being reported with lab testing results are appropriate and defensible.