The receipt of a PSA test and total serum PSA levels over time were extracted from electronic laboratory records and were determined to be elevated according to the established age-specific reference ranges for PSA. Prostate biopsies were extracted from the electronic medical record (CPT and ICD-9 procedure codes 60.11, 55700, 0137T). Incident prostate cancer was identified through the KPSC Cancer Registry, which provides data to the Surveillance, Epidemiology, and End Results (SEER) registry. Treatment for prostate cancer (surgery or radiation therapy) was identified via the cancer registry and was based on the first treatment received within 6 months of initial diagnosis. Age was also abstracted from the electronic health plan files and was categorized into 40-49, 50-64, 65-74, and ≥75years.