Rise and fall of radical prostatectomy rates from 1989 to 1996.

OBJECTIVES

To describe the changes in the rates of radical prostatectomy procedures, prostate-specific antigen (PSA) screening tests among Medicare beneficiaries, and the incidence of prostate cancer in the United States and to explain the exaggerated increase and decrease in the frequency of radical prostatectomy from 1989 to 1996.

METHODS

Medicare claims data on radical prostatectomy procedures and screening PSA tests and the National Cancer Institute's Surveillance, Epidemiology, and End Results prostate cancer incidence data were used to estimate the rates of PSA testing and radical prostatectomy among Medicare beneficiaries aged 65 to 74 years and 75 years and older (population rates). The age-specific true rates of the procedure were also estimated for the incident cases of prostate cancer (the population at risk of undergoing radical prostatectomy) among the beneficiaries.

RESULTS

The PSA test, prostate cancer incidence, and radical prostatectomy rates increased from 1989 to 1992. Thereafter, the incidence of prostate cancer, and the population and true rates of radical prostatectomy declined. The percentage of increase and decrease in the population rate of radical prostatectomy was approximately twice that in its true rate.

CONCLUSIONS

The radical prostatectomy rates based on all Medicare beneficiaries grossly exaggerated the changes in the use of the procedure. Where possible, true rates, using the population at risk as the denominator, should be used in the studies of diagnostic and therapeutic procedures, complications, and adverse effects.