TURKISH JOURNAL OF ONCOLOGY 2008 , Vol 23 , Num 1
The determination of reference values in biomarkers
Hakan ÇAMLICA, Rian DİŞÇİ
İstanbul Üniversitesi Onkoloji Enstitüsü, Kanser Epidemiyolojisi ve Biyoistatistik Bilim Dalı, İstanbul, Turkey Biomarkers are important molecular signatures of the phenotype of a cell that aid in early cancer detection and risk assessment. The diagnostic attribute of a test, diagnostic sensitivity and diagnostic specificity are important in accessing whether a test is useful. The concept of reference values was introduced to avoid the ambiguities inherent in the term “cuto ff values”. The reference interval is easily determined by both parametric and nonparametric statistical methods. An important and useful technique for evaluating the performance of diagnostic medical tests is the receiver operating characteristic (ROC) curve. ROC curves have become the standard for describing and comparing the accuracy of diagnostic tests. Keywords : Accuracy; biometry/methods; reference values; ROC; sensitivity; specificity