Alpert PF - Author evaluated if prostate cancer screening with PSA was beneficial in reducing prostate cancer mortality, and determined optimal screening intervals and age groups to be screened. This was the first study to evaluate various screening intervals and age groups and demonstrated that yearly screening was the interval of choice. In men with prostate cancer, to reduce both prostate cancer mortality and all-cause mortality, yearly PSA screening was highly effective. It provided support for PSA screening for men in good health, aged 55-75 when combined with active surveillance to prevent overtreatment.