Clsi Ep28 — [best]
The guideline, titled "Defining, Establishing, and Verifying Reference Intervals in the Clinical Laboratory," is the global gold standard for how medical laboratories determine the "normal ranges" used to interpret patient test results. Without these intervals, a blood sugar or cholesterol reading is just a number; the reference interval provides the context to decide if that number signifies health or disease. 1. The Core Purpose of EP28-A3c