osteoarthritis biomarkers, such as  serum cartilage oligomeric protein (sCOMP) and urinary C-telopeptide of type II collagen (uCTX-II), are used as indicators for osteoarthritis screening and as predictors for therapeutic responses and prognoses in patients. The trait is osteoarthritis biomarker measurement (Experimental Factor Ontology identifier EFO_0005890).