The NICE guideline35 concluded that PSA velocity, density, and % free PSA may be the best indicators to trigger further diagnostics in higher risk populations, however the “no screening” strategy seemed optimal for the lowest-risk subpopulation who had MRI Likert scores of 1 or 2 (very unlikely/unlikely that the patient has prostate cancer that needs to be treated) and 2 previous negative biopsies. This evidence concerns the gene KLK3 and prostate carcinoma.