Serum Prostate-Specific Antigen Measurement

For the current study, serum PSA concentration, measured in ng/mL, was determined using the Hybritech Total PSA Assay in the Beckman Access Immunoassay System (Beckman Coulter, Fullerton, CA) [27 (link)]. All male participants above 40 years were eligible to have their PSA levels assessed, except those with recent rectal examination within the preceding week, cystoscopy or prostate biopsy within the past month, ongoing prostate gland inflammation or infection, and any history of PCa [28 ]. Dichotomous ( < = 4 ng/mL or > 4 ng/mL) PSA data were used as outcome variables in our analyses. where 4 ng/mL is the current clinical cut-point for a positive screen [29 (link)–31 (link)].