For patients with pneumonia, the formula was logitP = −1.278 + 0.014 CEA + 0.004 CA125 + 0.028 CY211 + 0.019 NSE + 0.529 sex + 0.434 age (sex = 1 or 2 indicated males or females, respectively; for people aged less than 65, age = 1, and for those at the age of 65 or more than 65, age = 2). Here, ENO2 is linked to pneumonia.