Clsi Ep28 -

She called Mrs. Park’s family. The levothyroxine was stopped. The arrhythmia resolved.

Aliyah nodded. “But EP28 says if we have 120 subjects, nonparametric ranking is the gold standard. The 2.5th and 97.5th percentiles are 0.6 and 3.2. That’s our truth.” clsi ep28

Dr. Aliyah Vargas had run the University Hospital’s clinical chemistry lab for twelve years, and in that time, she had learned to trust two things: cold logic and the CLSI guidelines. EP28, specifically—the standard for defining, establishing, and verifying reference intervals—was her bible. It told her what “normal” looked like for a patient population. She called Mrs