Background: As the debate over the effectiveness of prostate-specific antigen (PSA) screening for prostate cancer continues, it is increasingly important to understand how PSA screening occurs in general-practice settings.
Methods: We conducted a retrospective cohort study within Kaiser Permanente Southern California, a large integrated health care system. Men aged 35 years and older at baseline, in 1998, were eligible. The proportion of men who underwent PSA screening was estimated and compared across groups defined by patient and physician characteristics. We also evaluated trends in screening across time and serum PSA levels for all subgroups.
Results: Of 2,061,047 men, 572,306 (28%) underwent PSA screening from 1998 through 2007. Patterns of PSA screening varied modestly by age, race, and physician. The lowest frequencies of screening occurred among men younger than age 45 years (19%) and men ages 85 years and older (13%). PSA screening was most common among white men (33.5%) and in men seen by physicians of the same race/ethnicity (32%), compared with men with physicians of disparate race/ethnicity (26%, p < 0.001). PSA screening increased over time for all racial/ethnic groups and among men age 75 years and older but decreased over time for men younger than age 75 years old.
Conclusions: Nearly 1 in 4 eligible men underwent PSA screening from 1998 through 2007, and screening varied only modestly by patient and physician characteristics. Estimates of the frequency of PSA screening in general-practice settings can inform the debate and provide useful insight as to how changes in cancer screening guidelines would alter practice patterns in an increasingly integrated health care environment.