1) The accuracy of the PSA test for detecting prostate cancer depends on the age of the patient and the prevalence of prostate cancer, which increases significantly with age. 2) For patients under 70 years old, the PSA test has very low accuracy, ranging from near 0% to 22% accuracy, which could lead to many unnecessary invasive biopsies. 3) The U.S. Preventive Services Task Force recommends against PSA-based prostate cancer screening for men 75 and older, and makes no recommendation for men under 75 due to inadequate evidence that screening improves health outcomes.