PURPOSE: We determined the biological variation of the total, free and percent free serum prostate specific antigen (PSA) in men 50 years old or older. MATERIALS AND METHODS: Between July 1995 and February 1996 we studied 84 healthy men from our PSA screening study to determine biological variation by calculating the coefficients of variation of 3 PSA measurements on blood samples drawn from each subject 2 weeks apart. RESULTS: The mean coefficients of variation for total, free and percent free serum PSA were 15, 17 and 14%, respectively. Age, total PSA and ejaculation were not confounding factors in this analysis (that is multivariate R2 less than 5% for all indexes). CONCLUSIONS: There is a mean variation of approximately 15% in measurements of total, free and percent free PSA that does not appear to be significantly affected by age and total PSA level.
PURPOSE: We determined the biological variation of the total, free and percent free serum prostate specific antigen (PSA) in men 50 years old or older. MATERIALS AND METHODS: Between July 1995 and February 1996 we studied 84 healthy men from our PSA screening study to determine biological variation by calculating the coefficients of variation of 3 PSA measurements on blood samples drawn from each subject 2 weeks apart. RESULTS: The mean coefficients of variation for total, free and percent free serum PSA were 15, 17 and 14%, respectively. Age, total PSA and ejaculation were not confounding factors in this analysis (that is multivariate R2 less than 5% for all indexes). CONCLUSIONS: There is a mean variation of approximately 15% in measurements of total, free and percent free PSA that does not appear to be significantly affected by age and total PSA level.
Authors: Anders Christensson; Laila Bruun; Thomas Björk; Angel M Cronin; Andrew J Vickers; Caroline J Savage; Hans Lilja Journal: BJU Int Date: 2010-10-18 Impact factor: 5.588
Authors: Behfar Ehdaie; Bing Ying Poon; Daniel D Sjoberg; Pedro Recabal; Vincent Laudone; Karim Touijer; James Eastham; Peter T Scardino Journal: BJU Int Date: 2015-10-26 Impact factor: 5.588
Authors: Donna Pauler Ankerst; Jonathan Gelfond; Martin Goros; Jesus Herrera; Andreas Strobl; Ian M Thompson; Javier Hernandez; Robin J Leach Journal: J Urol Date: 2016-03-12 Impact factor: 7.450